1.
San Francisco
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San Francisco, officially the City and County of San Francisco, is the cultural, commercial, and financial center of Northern California. It is the birthplace of the United Nations, the California Gold Rush of 1849 brought rapid growth, making it the largest city on the West Coast at the time. San Francisco became a consolidated city-county in 1856, after three-quarters of the city was destroyed by the 1906 earthquake and fire, San Francisco was quickly rebuilt, hosting the Panama-Pacific International Exposition nine years later. In World War II, San Francisco was a port of embarkation for service members shipping out to the Pacific Theater. Politically, the city votes strongly along liberal Democratic Party lines, San Francisco is also the headquarters of five major banking institutions and various other companies such as Levi Strauss & Co. Dolby, Airbnb, Weebly, Pacific Gas and Electric Company, Yelp, Pinterest, Twitter, Uber, Lyft, Mozilla, Wikimedia Foundation, as of 2016, San Francisco is ranked high on world liveability rankings. The earliest archaeological evidence of habitation of the territory of the city of San Francisco dates to 3000 BC. Upon independence from Spain in 1821, the became part of Mexico. Under Mexican rule, the system gradually ended, and its lands became privatized. In 1835, Englishman William Richardson erected the first independent homestead, together with Alcalde Francisco de Haro, he laid out a street plan for the expanded settlement, and the town, named Yerba Buena, began to attract American settlers. Commodore John D. Sloat claimed California for the United States on July 7,1846, during the Mexican–American War, montgomery arrived to claim Yerba Buena two days later. Yerba Buena was renamed San Francisco on January 30 of the next year, despite its attractive location as a port and naval base, San Francisco was still a small settlement with inhospitable geography. The California Gold Rush brought a flood of treasure seekers, with their sourdough bread in tow, prospectors accumulated in San Francisco over rival Benicia, raising the population from 1,000 in 1848 to 25,000 by December 1849. The promise of fabulous riches was so strong that crews on arriving vessels deserted and rushed off to the gold fields, leaving behind a forest of masts in San Francisco harbor. Some of these approximately 500 abandoned ships were used at times as storeships, saloons and hotels, many were left to rot, by 1851 the harbor was extended out into the bay by wharves while buildings were erected on piles among the ships. By 1870 Yerba Buena Cove had been filled to create new land, buried ships are occasionally exposed when foundations are dug for new buildings. California was quickly granted statehood in 1850 and the U. S. military built Fort Point at the Golden Gate, silver discoveries, including the Comstock Lode in Nevada in 1859, further drove rapid population growth. With hordes of fortune seekers streaming through the city, lawlessness was common, and the Barbary Coast section of town gained notoriety as a haven for criminals, prostitution, entrepreneurs sought to capitalize on the wealth generated by the Gold Rush
2.
California
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California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon, Nevada, and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California also has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire then claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence. The western portion of Alta California then was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, government, real estate services, technology, and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups also were diverse in their organization with bands, tribes, villages. Trade, intermarriage and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years later English explorer Francis Drake also explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
3.
United States
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Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
4.
Market Street Railway (transit operator)
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The Market Street Railway Company was a commercial streetcar and bus operator in San Francisco. The company was named after the famous Market Street of that city, over the years, the company was also known as the Market Street Railroad Company, the Market Street Cable Railway Company and the United Railroads of San Francisco. The franchise for what would become the Market Street Railway was granted in 1857 to Thomas Hayes, the line was the first horsecar line to open in San Francisco, opened on July 4,1860, as the Market Street Railroad Company. A few years later, the line was converted to steam power utilizing an engine that was part locomotive and part passenger car. Following the opening of the cable hauled Clay Street Hill Railroad in 1873, in 1882, Leland Stanford and associates bought the Market Street Railroad Company and converted its lines to cable haulage. In the process, the name was changed to the Market Street Cable Railway Company. This company was to grow to become San Franciscos largest cable car operator, at its peak, it operated five lines all of which converged into Market Street to a common terminus at the Ferry Building, during rush hours a cable car left that terminus every 15 seconds. In 1893, Stanford died and the company was taken over by the Southern Pacific Railroad, the company was again renamed to the Market Street Railway Company, and began the process of converting its lines to electric traction. In 1895 the company placed an advertisement in the San Francisco Examiner offering horse cars for $20. Many of these became the basis for the community built from streetcars called Carville-by-the-Sea. Conversion to electricity was resisted by opponents who objected to what they saw as ugly overhead lines on the thoroughfares of the city center. At 5,12 am on April 18,1906, those objections were swept away as the great San Francisco earthquake struck, the race to rebuild the city allowed the company to replace all but the steepest of its cable car lines with electric streetcar lines. By this stage, the company had changed again. Horsecars were finally withdrawn from city streets on June 3,1914, by 1918, and assisted by the construction of several tunnels under the citys hills, Muni was in direct competition with the URR down the length of Market Street. The two operators each operated their own pair of tracks down that thoroughfare, which came to be known as the roar of the four. The two Market Street Railway tracks were on the inside and the two San Francisco Municipal Railway tracks were on the outside, competition, labor troubles and a bad accident in 1918 led to the reorganisation of the URR, to re-emerge again as the Market Street Railway Company. This continued to operate electric streetcars throughout the city, the Powell St. cable car lines, and a fleet of buses.5 million. These are the surviving vehicles from the Market Street Railway fleet, Car 578 was built in 1896 by the Hammond Car Company and is a single-truck
5.
San Francisco Municipal Railway
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The San Francisco Municipal Railway is the public transit system for the city and county of San Francisco, California. In 2006, it served 46.7 square miles with an budget of about $700 million. In ridership Muni is the seventh largest transit system in the United States, with 210,848,310 rides in 2006 and the second largest in California behind Metro in Los Angeles. With a fleet average speed of 8.1 mph, it is the slowest major urban transit system in America and one of the most expensive to operate, costing $19.21 per mile per bus and $24.37 per mile per train. However, it has more boardings per mile and more vehicles in operation than similar transit agencies, many weekday riders are commuters, as the daytime weekday population in San Francisco exceeds its normal residential population. Muni shares four metro stations with BART, on weekends, most Muni bus lines are scheduled to run every ten to twenty minutes. However, complaints of unreliability, especially on less-often-served lines and older lines, are a system-wide problem. Muni has had difficulty meeting a stated goal of 85% voter-demanded on-time service. Most intercity connections are provided by BART and Caltrain heavy rail, AC Transit buses at the Transbay Terminal, 70% of stops are spaced closer than recommended range of 800–1,000 feet apart. Muni is short for the Municipal in San Francisco Municipal Railway and is not an acronym, thus, the Muni metro is often called the train or the streetcar. Most San Francisco natives use Muni when speaking about the system in general, the E Embarcadero and F Market & Wharves lines are referred to by Muni as a historic streetcar line rather than as a heritage railway. Munis logo is a stylized, trademarked worm version of the word muni and this logo was designed by San Francisco-based graphic designer Walter Landor in the mid-1970s. Bus and trolleybus lines have number designations, rail lines have letters, except for cable cars, cash fares are $2.50 for adults, $1. Clipper card fares are $2.25 for adults and $1 for seniors, youth, proof-of-payment, which fare inspectors may demand at any time, is either a Clipper card, Muni Passport, or paper transfer. One fare entitles a rider to unlimited vehicle transfers for the next 90 to 120 minutes, cable cars are $7 one way, with no transfers unless the rider has a Muni Passport or Fast Pass. As of September 2014 monthly passes cost $70 for adults, $35 for low-income residents, or $24 for youth, seniors, passes are valid on all Muni lines—including cable cars—and the $83 adult Fast Pass allows BART transit entirely within San Francisco. Other passes and stickers are valid on all Muni lines, including cable cars, cable car fare is $7 per trip, with no transfers issued or accepted. Muni has implemented a smart card payment system known as Clipper
6.
Railway electrification system
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A railway electrification system supplies electric power to railway trains and trams without an on-board prime mover or local fuel supply. Electrification has many advantages but requires significant capital expenditure, selection of an electrification system is based on economics of energy supply, maintenance, and capital cost compared to the revenue obtained for freight and passenger traffic. Different systems are used for urban and intercity areas, some electric locomotives can switch to different supply voltages to allow flexibility in operation, Electric railways use electric locomotives to haul passengers or freight in separate cars or electric multiple units, passenger cars with their own motors. Electricity is typically generated in large and relatively efficient generating stations, transmitted to the railway network, some electric railways have their own dedicated generating stations and transmission lines but most purchase power from an electric utility. The railway usually provides its own lines, switches and transformers. Power is supplied to moving trains with a continuous conductor running along the track usually takes one of two forms. The first is a line or catenary wire suspended from poles or towers along the track or from structure or tunnel ceilings. Locomotives or multiple units pick up power from the wire with pantographs on their roofs that press a conductive strip against it with a spring or air pressure. Examples are described later in this article, the second is a third rail mounted at track level and contacted by a sliding pickup shoe. Both overhead wire and third-rail systems usually use the rails as the return conductor. In comparison to the alternative, the diesel engine, electric railways offer substantially better energy efficiency, lower emissions. Electric locomotives are usually quieter, more powerful, and more responsive and they have no local emissions, an important advantage in tunnels and urban areas. Different regions may use different supply voltages and frequencies, complicating through service, the limited clearances available under catenaries may preclude efficient double-stack container service. Possible lethal electric current due to risk of contact with high-voltage contact wires, overhead wires are safer than third rails, but they are often considered unsightly. These are independent of the system used, so that. The permissible range of voltages allowed for the voltages is as stated in standards BS EN50163. These take into account the number of trains drawing current and their distance from the substation, railways must operate at variable speeds. Until the mid 1980s this was only practical with the brush-type DC motor, since such conversion was not well developed in the late 19th century and early 20th century, most early electrified railways used DC and many still do, particularly rapid transit and trams
7.
Volt
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The volt is the derived unit for electric potential, electric potential difference, and electromotive force. One volt is defined as the difference in potential between two points of a conducting wire when an electric current of one ampere dissipates one watt of power between those points. It is also equal to the difference between two parallel, infinite planes spaced 1 meter apart that create an electric field of 1 newton per coulomb. Additionally, it is the difference between two points that will impart one joule of energy per coulomb of charge that passes through it. It can also be expressed as amperes times ohms, watts per ampere, or joules per coulomb, for the Josephson constant, KJ = 2e/h, the conventional value KJ-90 is used, K J-90 =0.4835979 GHz μ V. This standard is typically realized using an array of several thousand or tens of thousands of junctions. Empirically, several experiments have shown that the method is independent of device design, material, measurement setup, etc. in the water-flow analogy sometimes used to explain electric circuits by comparing them with water-filled pipes, voltage is likened to difference in water pressure. Current is proportional to the diameter of the pipe or the amount of water flowing at that pressure. A resistor would be a reduced diameter somewhere in the piping, the relationship between voltage and current is defined by Ohms Law. Ohms Law is analogous to the Hagen–Poiseuille equation, as both are linear models relating flux and potential in their respective systems, the voltage produced by each electrochemical cell in a battery is determined by the chemistry of that cell. Cells can be combined in series for multiples of that voltage, mechanical generators can usually be constructed to any voltage in a range of feasibility. High-voltage electric power lines,110 kV and up Lightning, Varies greatly. Volta had determined that the most effective pair of metals to produce electricity was zinc. In 1861, Latimer Clark and Sir Charles Bright coined the name volt for the unit of resistance, by 1873, the British Association for the Advancement of Science had defined the volt, ohm, and farad. In 1881, the International Electrical Congress, now the International Electrotechnical Commission and they made the volt equal to 108 cgs units of voltage, the cgs system at the time being the customary system of units in science. At that time, the volt was defined as the difference across a conductor when a current of one ampere dissipates one watt of power. The international volt was defined in 1893 as 1/1.434 of the emf of a Clark cell and this definition was abandoned in 1908 in favor of a definition based on the international ohm and international ampere until the entire set of reproducible units was abandoned in 1948. Prior to the development of the Josephson junction voltage standard, the volt was maintained in laboratories using specially constructed batteries called standard cells
8.
Direct current
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Direct current is a flow of electrical charge carriers that always takes place in the same direction. The current need not always have the magnitude, but if it is to be defined as dc. This contrasts with alternating current which varies the direction of flow, sources of direct current include power supplies, electrochemical cells and batteries, and photovoltaic cells and panels. The intensity, or amplitude, of a direct current might fluctuate with time, in some such cases the dc has an ac component superimposed on it. An example of this is the output of a cell that receives a modulated light communications signal. A source of dc is sometimes called a dc generator, batteries and various other sources of dc produce a constant voltage. This is called pure dc and can be represented by a straight, the peak and effective values are the same. The peak to peak value is zero because the instantaneous amplitude never changes, in some instances the value of a dc voltage pulsates or oscillates rapidly with time, in a manner similar to the changes in an ac wave. The unfiltered output of a wave or a full wave rectifier. In 1820, Hans Christian Orsted discovered that electrical current creates a magnetic field and this discovery made scientists relate magnetism to the electric phenomena. In 1879, Thomas Edison invented the light bulb. He improved a 50-year-old idea using lower current electricity, a vacuum inside the globe and a small carbonized filament. At that time, the idea of lightning was not new. Edison not only invented an incandescent electric light, but an electric lighting system contained all the necessary elements to make the incandescent light safe, economical. Prior to 1879, direct current electricity had been used in lighting for the outdoors and it was in the 1880s when the modern electric utility industry began. It was an evolution from street lighting systems and from gas and it was located in Lower Manhattan, on Pearl Street. This station provided light and electricity to customers in a one square mile range, the station was called Thomas Edisons Pearl Street Electricity Generating Station. This station introduced four elements of an electric utility system, Efficient distribution, competitive price, reliable central generation
9.
Overhead line
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An overhead line or overhead wire is used to transmit electrical energy to trams, trolleybuses, or trains. Overhead line is designed on the principle of one or more overhead wires situated over rail tracks, the feeder stations are usually fed from a high-voltage electrical grid. Electric trains that collect their current from overhead lines use a device such as a pantograph and it presses against the underside of the lowest overhead wire, the contact wire. Current collectors are electrically conductive and allow current to flow through to the train or tram, non-electric locomotives may pass along these tracks without affecting the overhead line, although there may be difficulties with overhead clearance. Alternative electrical power transmission schemes for trains include third rail, ground-level power supply, batteries and this article does not cover regenerative braking, where the traction motors act as generators to retard movement and return power to the overhead. To achieve good high-speed current collection, it is necessary to keep the wire geometry within defined limits. This is usually achieved by supporting the wire from a second wire known as the messenger wire or catenary. This wire approximates the path of a wire strung between two points, a catenary curve, thus the use of catenary to describe this wire or sometimes the whole system. This wire is attached to the wire at regular intervals by vertical wires known as droppers or drop wires. It is supported regularly at structures, by a pulley, link, the whole system is then subjected to a mechanical tension. As the contact wire makes contact with the pantograph, the insert on top of the pantograph is worn down. The straight wire between supports will cause the wire to cross over the whole surface of the pantograph as the train travels around the curve, causing uniform wear. On straight track, the wire is zigzagged slightly to the left. The movement of the wire across the head of the pantograph is called the sweep. The zigzagging of the line is not required for trolley poles. Depot areas tend to have only a wire and are known as simple equipment or trolley wire. When overhead line systems were first conceived, good current collection was only at low speeds. Compound equipment - uses a second wire, known as the auxiliary
10.
Electric Transit, Inc.
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ETI was formed in 1994, and ownership was divided as 65% by Škoda and 35% by AAI. The latter was a wholly owned subsidiary of United Industrial Corporation, up to that time, Škoda had built more than 12,000 trolleybuses since 1935, but none for cities outside Europe and Asia. The company was awarded its first contract in November 1994, when the Miami Valley Regional Transit Authority, of Dayton, the order was later reduced to 61 vehicles, and ultimately to 57. Three prototype trolleybuses were delivered in December 1995 and January 1996 and these were designated by ETI as model 14TrE, the E standing for export, and were given fleet numbers 9601-9603 by MVRTA. Following modifications to the design, construction of the 54 production-series ETI trolleybuses for Dayton took place in 1998-99 and these were model 14TrE2 and were numbered 9801-9854 in MVRTAs fleet. In July 1997, the San Francisco Municipal Railway contracted with ETI for the provision of 250 trolleybuses, ETI designated the two types for San Francisco as models 14TrSF and 15TrSF, respectively. In February 2000, Muni exercised contract options to purchase an additional 20 two-axle, two prototypes for the two-axle trolleybuses were received by Muni in January 1999 and June 1999, respectively, while an articulated prototype was received in April 2000. The 238 production-series two-axle trolleybuses were delivered between May 2001 and early 2004, the production-series articulateds were all delivered in 2003. All 273 of Munis ETI trolleybuses had entered service by April 2004, except in the case of the prototypes, final fitting-out was undertaken in leased premises located in the two cities purchasing the vehicles, Dayton and San Francisco. In 2003, ETI engaged in a bidding for a large contract being offered by TransLink, of Vancouver. Canada for supply of trolleybuses to the Vancouver trolleybus system, the joint venture did not seek any further new business, and in May 2004 it finalized an agreement with San Francisco Muni to transfer to Muni its remaining contractual obligations. List of trolleybus manufacturers United Streetcar – another joint venture between Škoda and a U. S. company Various issues, Trolleybus Magazine. United Industrial Corp. profile on Funding Universe, retrieved 2009-06-20 Skoda manufactures trolley busses for San Francisco -2001 audio clips from Radio Prague, retrieved 2009-06-20
11.
Nob Hill, San Francisco
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Nob Hill is a neighborhood in San Francisco, California, centered on the intersection of California Street and Powell Street. It is one of San Franciscos 44 hills, and one of its original Seven Hills, prior to the 1850s, Nob Hill was called California Hill. It was renamed after the Central Pacific Railroads Big Four – called the Nobs – built mansions there, the actual peak of Nob Hill lies slightly to the northwest, approximately at the intersection of Jones and Sacramento Streets. South of Nob Hill is Lower Nob Hill neighborhood, the district of Union Square, the Tenderloin neighborhood. To the east is San Franciscos Chinatown and a little farther, northeast of Nob Hill is North Beach and Telegraph Hill. North of Nob Hill is Russian Hill, and eventually, the areas of the waterfront such as Pier 39. The area was settled in the rapid urbanization happening in the city in the late 19th century, because of the views and its central position, it became an exclusive enclave of the rich and famous on the west coast who built large mansions in the neighborhood. This included prominent tycoons such as Leland Stanford, founder of Stanford University, for this reason, its early citizens were known as nabobs, which was shortened to nob, giving the area its eventual name. The neighborhood was destroyed in the 1906 earthquake and fire, except for the walls surrounding the Stanford, Crocker, Huntington. Those walls remain and black caused by smoke from the intense fires that burned after the quake can still be seen. Also gutted by the fires was the newly completed Fairmont Hotel at Mason and California Streets, both structures had stone exteriors that survived the fires, and both buildings were subsequently cleaned and refurbished. The Fairmont Hotel remains in operation to day and the Flood Mansion is the headquarters of the exclusive Pacific-Union Club. While the neighborhood was able to maintain its affluence following the quake, some rebuilt mansions further west in San Francisco, for example, in Pacific Heights and Cow Hollow. In place of where the mansions had been located, swank hotels were erected, hotels built over the ruins of the former mansions include the Mark Hopkins, Huntington and Stanford Court. Nob is disparaging British slang abbreviation of noble/nobility referring to the monied, the location is also derisively referred to as Snob Hill. The intersection of California and Powell streets is the location of two of its four well-known and most expensive hotels, the Fairmont Hotel, the Mark Hopkins Hotel, the Mark Hopkins Hotel and the Huntington Hotel are located one block away at Mason & California. The hotels were named for three of The Big Four, four entrepreneurs of the construction of the Central Pacific Railroad, Leland Stanford, the fourth, Charles Crocker has a garage named after him in the neighborhood. The Fairmont is also named for a San Francisco tycoon, James G. Fair, opposite the Fairmont Hotel and Pacific Union Club is Grace Cathedral, one of the citys largest houses of worship
12.
Grade (slope)
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The grade of a physical feature, landform or constructed line refers to the tangent of the angle of that surface to the horizontal. It is a case of the slope, where zero indicates horizontality. A larger number indicates higher or steeper degree of tilt, often slope is calculated as a ratio of rise to run, or as a fraction in which run is the horizontal distance and rise is the vertical distance. The grades or slopes of existing physical features such as canyons and hillsides, stream and river banks, grades are typically specified for new linear constructions. The grade may refer to the slope or the perpendicular cross slope. There are several ways to express slope, as an angle of inclination to the horizontal, as a percentage, the formula for which is 100 rise run which could also be expressed as the tangent of the angle of inclination times 100. In the U. S. this percentage grade is the most commonly used unit for communicating slopes in transportation, surveying, construction, and civil engineering. As a per mille figure, the formula for which is 1000 rise run which could also be expressed as the tangent of the angle of inclination times 1000 and this is commonly used in Europe to denote the incline of a railway. As a ratio of one part rise to so many parts run, for example, a slope that has a rise of 5 feet for every 100 feet of run would have a slope ratio of 1 in 20. This is generally the method used to describe railway grades in Australia, any of these may be used. Grade is usually expressed as a percentage, but this is converted to the angle α from horizontal or the other expressions. Slope may still be expressed when the run is not known. This is not the way to specify slope, it follows the sine function rather than the tangent function. But in practice the way to calculate slope is to measure the distance along the slope and the vertical rise. When the angle of inclination is small, using the slope length rather than the horizontal displacement makes only an insignificant difference, Railway gradients are usually expressed in terms of the rise in relation to the distance along the track as a practical measure. In cases where the difference between sin and tan is significant, the tangent is used. In any case, the identity holds for all inclinations up to 90 degrees, tan α = sin α1 − sin 2 α In Europe. Grades are related using the equations with symbols from the figure at top
13.
Trolleybus
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A trolleybus is an electric bus that draws power from overhead wires using spring-loaded trolley poles. Two wires and poles are required to complete the electrical circuit and this differs from a tram or streetcar, which normally uses the track as the return path, needing only one wire and one pole. They are also distinct from other kinds of buses, which usually rely on batteries. Power is most commonly supplied as 600-volt direct current, but there have been, currently, around 300 trolleybus systems are in operation, in cities and towns in 43 countries. Altogether, more than 800 trolleybus systems have existed, but not more than about 400 concurrently, the trolleybus dates back to 29 April 1882, when Dr. Ernst Werner Siemens demonstrated his Elektromote in a Berlin suburb. This experiment continued until 13 June 1882, after there were few developments in Europe. In 1899, another vehicle which could run either on or off rails was demonstrated in Berlin, routes followed in Eberswalde and Fontainebleau. Max Schiemann on 10 July 1901 opened the worlds fourth passenger-carrying trolleybus system, although this system operated only until 1904, Schiemann had developed what is now the standard trolleybus current collection system. In the early days there were a few methods of current collection. The Cédès-Stoll system was operated near Dresden between 1902 and 1904, and in Vienna, the Lloyd-Köhler or Bremen system was tried out in Bremen, and the Cantono Frigerio system was demonstrated near Milan. Throughout the period, trackless freight systems and electric canal boats were also built, Leeds and Bradford became the first cities to put trolleybuses into service in Great Britain on 20 June 1911. Apparently, though it was opened on 20 June, the public was not admitted to the Bradford route until the 24th, Bradford was also the last to operate trolleybuses in the UK, the system closing on 26 March 1972. The last rear-entrance trolleybus in Britain was also in Bradford and is now owned by the Bradford Trolleybus Association, birmingham was the first to replace a tram route with trolleybuses, while Wolverhampton, under the direction of Charles Owen Silvers, became world-famous for its trolleybus designs. There were 50 trolleybus systems in the UK, Londons being the largest, by the time trolleybuses arrived in Britain in 1911, the Schiemann system was well established and was the most common, although the Cédès-Stoll system was tried in West Ham and in Keighley. Smaller trackless trolley systems were built in the US early as well, the trackless trolley was often seen as an interim step, leading to streetcars. Buses and trolleybuses in particular were seen as entry systems that could later be upgraded to rail as appropriate, some trolleybus lines in the United States came into existence when a trolley or tram route did not have sufficient ridership to warrant track maintenance or reconstruction. In a similar manner, a proposed tram scheme in Leeds, worldwide, around 300 cities or metropolitan areas are served by trolleybuses today. See also Trolleybus usage by country, for example, new systems opened in Lecce, Italy, in 2012 and in Malatya, Turkey, in 2015
14.
Public transport
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Public transport modes include city buses, trolleybuses, trams and passenger trains, rapid transit and ferries. Public transport between cities is dominated by airlines, coaches, and intercity rail, high-speed rail networks are being developed in many parts of the world. Most public transport runs to a timetable, with the most frequent services running to a headway. Share taxis offer services in many parts of the world. Paratransit is sometimes used in areas of low demand and for people who need a door-to-door service, there are distinct differences in urban public transit between Asia, North America, and Europe. In Asia, mass transit operations are run by profit-driven privately owned and publicly traded mass transit. In North America, mass transit operations are run by municipal transit authorities. In Europe, mass transit operations are run by both state-owned and private companies. Public transport services can be profit-driven by use of pay-by-the-distance fares or funded by government subsidies in which flat rate fares are charged to each passenger. Services can be profitable through high ridership numbers and high farebox recovery ratios, or can be regulated. Fully subsidized, zero-fare services operate in some towns and cities, for geographical, historical and economic reasons, there are differences internationally regarding use and extent of public transport. It has 3,400 members from 92 countries, conveyances designed for public hire are as old as the first ferries, and the earliest public transport was water transport, on land people walked or rode an animal. Ferries appear in Greek mythology—corpses in ancient Greece were buried with a coin underneath their tongue to pay the ferryman Charon to take them to Hades, the omnibus was introduced to London in July 1829. The first passenger railway opened in 1806, it ran between Swansea and Mumbles in southwest Wales in the United Kingdom. In 1825 George Stephenson built the Locomotion for the Stockton and Darlington Railway in northeast England, the usability of different types of public transport, and its overall appeal, can be measured by seven criteria, although they overlap somewhat. These are speed, comfort, safety, cost, proximity, speed is calculated from total journey time including transfers. Proximity means how far passengers have to walk or otherwise travel before they can begin the public transport leg of their journey, timeliness is how long they have to wait for the vehicle. Directness records how far a journey using public transport deviates from the shortest route, an airline provides scheduled service with aircraft between airports
15.
States of the United States
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The United States of America is a federal republic consisting of 50 states, a federal district, five major territories, and various possessions. The 48 contiguous states and Washington, D. C. are in central North America between Canada and Mexico, the state of Alaska is in the northwestern part of North America and the state of Hawaii is an archipelago in the mid-Pacific. The territories are scattered about the Pacific Ocean and the Caribbean Sea, each state has its own constitution, grounded in republican principles, and government, consisting of three branches, executive, legislative, and judicial. All states and their residents are represented in the federal Congress, a legislature consisting of the Senate. Each state is represented by two Senators, while Representatives are distributed among the states in proportion to the most recent constitutionally mandated decennial census, Article IV, Section 3, Clause 1 of the Constitution grants to Congress the authority to admit new states into the Union. Since the establishment of the United States in 1776, the number of states has expanded from the original 13 to 50, each new state has been admitted on an equal footing with the existing states. As provided by Article I, Section 8 of the Constitution, Congress exercises exclusive jurisdiction over the federal district, which is not part of any state. Prior to passage of the 1973 District of Columbia Home Rule Act, which devolved certain Congressional powers to a mayor and council. Even so, Congress retains the right to review and overturn laws created by the council, as it is not a state, the district does not have representation in the Senate. However, since 1971, its residents have been represented in the House of Representatives by a non-voting delegate, additionally, since 1961, following ratification of the 23rd Amendment, the district has been entitled to select three electors to vote in the Electoral College. In addition to the 50 states and federal district, the United States has sovereignty over 14 territories, five of them have a permanent, nonmilitary population, while nine of them do not. With the exception of Navassa Island, Puerto Rico, and the U. S. Virgin Islands, Navassa Island is claimed by Haiti. The five inhabited territories each have limited autonomy in addition to having territorial legislatures and governors, california is the most populous state, with 38,332,521 residents, Wyoming is the least populous, with an estimated 582,658 residents. The District of Columbia, with an estimated 646,449 residents as of 2012, has a population than the two least populous states. The largest state by area is Alaska, encompassing 665,384 square miles, while the smallest is Rhode Island, encompassing 1,545 square miles. The first state to ratify the current Constitution was Delaware, which it did on December 7,1787, while the newest state is Hawaii, which was admitted to the Union on August 21,1959. The largest territory in terms of population and size is Puerto Rico, with 3,725,789 residents as of the 2010 Census. The most recent entity to come under the sovereignty of the United States in its current form is the Northern Mariana Islands, which formally did so on November 3,1986. S
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Muni Metro
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Muni Metro is a light rail/streetcar hybrid system serving San Francisco, California, operated by the San Francisco Municipal Railway, a division of the San Francisco Municipal Transportation Agency. With an average ridership of 128,500 passengers as of the fourth quarter of 2014. Muni Metro operates a fleet of 151 light rail vehicles made by Breda, Muni Metro is the modern incarnation of the traditional streetcar system that had served San Francisco since the late 19th century. Recently, the system has undergone expansion, most notably the Third Street Light Rail Project, completed in 2007, other projects, such as the Central Subway, are underway. Muni Metro descended from the traditional streetcar system started on December 28,1912. The first streetcar line, the A Geary, ran from Kearny and Market Streets in the Financial District to Fulton Street, the system slowly expanded, opening the Twin Peaks Tunnel in 1917, allowing streetcars to run to the southwestern quadrant of the city. By 1921, the city was operating 304 miles of trolley lines and 25 miles of cable car lines. The last line to service before 2007 was the N Judah. However, five heavily used streetcar lines traveled for at least part of their routes through tunnels or otherwise reserved right-of-way, as a result, these lines, running PCC streetcars, continued in operation. The new tunnel would be connected to the existing Twin Peaks Tunnel, the new underground stations would feature high platforms, and the older stations would be retrofitted with the same, which meant that the PCCs could not be used in them. Hence, a fleet of new rail vehicles was ordered from Boeing-Vertol. The K and M lines were extended to Balboa Park during this time, on February 18,1980, the Muni Metro was officially inaugurated, with weekday N line service in the subway. The Metro service was implemented in phases, and the subway was served only on weekdays until 1982. The K Ingleside line began using the Metro subway on weekdays on June 11,1980, the L Taraval and M Ocean View lines on December 17,1980, and lastly the J Church line on June 17,1981. Meanwhile, weekend service on all five lines continued to use PCC cars operating on the surface of Market Street through to the Transbay Terminal, finally, on November 20,1982, the Muni Metro subway began operating seven days a week. At the time, there were no plans to revive any service on the surface of Market Street or return PCCs to regular running. However, tracks were rehabilitated for the 1983 Historic Trolley Festival, Muni criticism had been something of a feature of life in San Francisco, and not without reason. The Boeing trains were sub-par and grew crowded quickly, Muni did take steps to address these problems
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San Francisco cable car system
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The San Francisco cable car system is the worlds last manually operated cable car system. An icon of San Francisco, the car system forms part of the intermodal urban transport network operated by the San Francisco Municipal Railway. Of the 23 lines established between 1873 and 1890, only three remain, two routes from downtown near Union Square to Fishermans Wharf, and a route along California Street. While the cable cars are used to an extent by commuters. They are among the most significant tourist attractions in the city, along with Alcatraz Island, the Golden Gate Bridge, the cable cars are listed on the National Register of Historic Places. The cable cars are not to be confused with San Franciscos heritage streetcars, which operate on Market Street, the first successful cable-operated street railway was the Clay Street Hill Railroad, which opened on August 2,1873. The promoter of the line was Hallidie, and the engineer was William Eppelsheimer, the line involved the use of grip cars, which carried the grip that engaged with the cable, towing trailer cars, the design was the first to use grips. The term grip became synonymous with the operator, the line started regular service on September 1,1873, and its success led it to become the template for other cable car transit systems. It was a success, and Hallidies patents were enforced on other cable car promoters. Accounts differ as to exactly how involved Hallidie was in the inception of the line, the next cable car line to open was the Sutter Street Railway, which converted from horse operation in 1877. This line introduced the side grip, and lever operation, both designed by Henry Casebolt and his assistant Asa Hovey, and patented by Henry Casebolt. This idea was brought about because Casebolt did not want to pay Hallidie royalties of $50,000 a year for use of his patent, the side grip allowed cable cars to cross at intersections. In 1878, Leland Stanford opened his California Street Cable Railroad and this companys first line was on California Street and is the oldest cable car line still in operation. In 1880, the Geary Street, Park & Ocean Railway began operation, the Presidio and Ferries Railway followed two years later, and was the first cable company to include curves on its routes. The curves were let-go curves, where the car drops the cable, in 1883, the Market Street Cable Railway opened its first line. This company was controlled by the Southern Pacific Railroad and was to grow to become San Franciscos largest cable car operator. At its peak, it operated five lines all of which converged into Market Street to a terminus at the Ferry Building, during rush hours, cars left that terminus every 15 seconds. In 1888, the Ferries and Cliff House Railway opened its initial two-line system, the Powell-Mason line is still operated on the same route today, their other route was the Powell-Washington-Jackson line, stretches of which are used by todays Powell-Hyde line
18.
Caltrain
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Caltrain is a California commuter rail line on the San Francisco Peninsula and in the Santa Clara Valley. The northern terminus of the line is in San Francisco at 4th, extra trains were often run for special events held in AT&T Park in San Francisco, Stanford Stadium in Palo Alto, and SAP Center in San Jose. Caltrain operates 92 weekday trains,6 of which are extended to Gilroy, weekday ridership in February 2016 averaged 62,416, up 83% since 2010. Caltrain is governed by the Peninsula Corridor Joint Powers Board which consists of agencies from the three counties served by Caltrain, San Francisco, San Mateo and Santa Clara, each member agency has three representatives on a nine-member Board of Directors. The member agencies are the City and County of San Francisco, SamTrans, Caltrain has 29 regular stops, one football-only stop, and two weekend-only stops. As of October 2012 Caltrain runs 92 weekday trains,36 Saturday, the original commuter railroad built in 1863 was the San Francisco and San Jose Rail Road, it was purchased by Southern Pacific in 1870. Southern Pacific double-tracked the line in 1904 and rerouted it via Bayshore, after 1945, ridership declined with the rise in automobile use, in 1977 SP petitioned the state Public Utilities Commission to discontinue the commute operation because of ongoing losses. To preserve the service, in 1980 Caltrans contracted with SP. Caltrans purchased new locomotives and rolling stock, replacing SP equipment in 1985, Caltrans also upgraded stations, added shuttle buses to nearby employers, and dubbed the operation CalTrain. The Peninsula Corridor Joint Powers Board was formed in 1987 to manage the line, subsequently, San Mateo and Santa Clara Counties commissioned Earth Metrics, Inc. to prepare an Environmental Impact Report on right-of-way acquisition and expansion of operations. With state and local funding, the PCJPB bought the right of way between San Francisco and San Jose from SP in 1991. The following year, PCJPB took responsibility for CalTrain operations and selected Amtrak as the contract operator, PCJPB extended the CalTrain service from San Jose to Gilroy, connecting to VTA Light Rail at Tamien Station in San Jose. In July 1995 CalTrain became accessible to passengers in wheelchairs, five months later, CalTrain increased the bicycle limit to 24 per train, making the service attractive to commuters in bicycle-friendly cities such as San Francisco and Palo Alto. In July 1997 the current logo was adopted, and the name became Caltrain. A year later, VTA extended its rail service from north Santa Clara to the Mountain View Caltrain station. In June 2003, a connection for the Bay Area Rapid Transit. In 2006, Caltrain announced that wireless internet access would be available on trains at no additional charge, Caltrain invested more than $1 million in researching and testing WiFi in 2006. Caltrain still hopes to offer the service eventually as part of a comprehensive communication package
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Bay Area Rapid Transit
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Bay Area Rapid Transit is a public transportation system serving the San Francisco Bay Area. The rapid transit elevated and subway system connects San Francisco with cities in Alameda, Contra Costa, BART operates 5 routes on 104 miles of track connecting 45 stations, plus a 3. 2-mile automated guideway transit line to the Oakland International Airport which adds an additional station. A spur line in eastern Contra Costa County will utilize other rail technologies, with an average of 433,000 weekday passengers and 128.5 million annual passengers in fiscal year 2016, BART is the fifth-busiest heavy rail rapid transit system in the United States. The systems acronym is pronounced Bart, like the name, BART is operated by the San Francisco Bay Area Rapid Transit District, formed in 1957. As of 2017, it is being expanded to San Jose with the consecutive Warm Springs, some of the Bay Area Rapid Transit Systems current coverage area was once served by an electrified streetcar and suburban train system called the Key System. This early 20th-century system once had regular trans-bay traffic across the deck of the Bay Bridge. By the mid-1950s, that system had been dismantled in favor of highway travel, a new rapid-transit system was proposed to take the place of the Key System during the late 1940s, and formal planning for it began in the 1950s. Some funding was secured for the BART system in 1959, passenger service began on September 11,1972, initially just between MacArthur and Fremont. All nine Bay Area counties were involved in the planning and envisioned to be connected by BART, before the system began revenue service, serious problems in the design and operation of the Automatic Train Control system were observed. Three engineers working for BART, Max Blankenzee, Robert Bruder, BART management was dismissive of their concerns, so the three took the issue to the board of directors. All but two of the directors voted in February 1972 to support management and reject the safety concerns, management retaliated against the engineers, firing them in March 1972. The IEEE later filed the first amicus brief in its history to support the engineers. The California Society of Professional Engineers reported to the California State Senate in June 1972 that there were serious safety risks with the ATC. Legislative analyst A. Alan Post, opened an investigation immediately, an ATC failure caused the train to run off the end of the elevated track and crash to the ground, injuring four people on-board, and drawing national and international attention. The “Fremont Flyer” led to a redesign of the train controls. The California State Public Utilities Commission imposed stringent oversight over train operations, the legislative analyst issued the first of three “Post Reports” in November 1972. The report was “sharply critical” of BART, finding that the ATC system was unreliable, the ATC program was mismanaged, and “no solution was in sight. ”The report accused BART of paying excessive fees for engineering services. BART’s general manager called the indictment of safety in the Post Report “not only disappointing, telephone calls were placed manually between stations, instead
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F Market & Wharves
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The F Market & Wharves line is one of several light rail lines in San Francisco, California. Despite its heritage status, the F Market & Wharves line is an part of Munis intermodal urban transport network, operating at frequent intervals for 20 hours a day. It carries local commuters and tourists alike, linking residential, business, unlike the San Francisco cable car system, standard Muni fares are levied. The streetcar line was discontinued in 1951 and was replaced by the 30-Stockton route, the F-line designation was therefore available for use by the current line, although that service is over a completely different route from the F-line of 1915 to 1951. Market Street is a major artery for the city of San Francisco. In the 1960s construction began on the Market Street Subway, which would carry BARTs trains on its lower level, all streetcar lines currently operating in the subway previously ran on the surface of Market Street, and were eventually diverted into the upper level of the tunnel. This diversion, together with the provision of new rail cars. The diversion of the Market Street streetcar lines into tunnel and the replacement of the existing streetcars with new rail cars was completed by November 1982. However, the trackage on Market Street was retained. In 1982, San Franciscos cable car lines were shut down for almost two years to allow for a major rebuild, to provide an alternative tourist attraction during this period, the San Francisco Historic Trolley Festivals began in 1983. These summertime operations of vintage streetcars on Market Street were a joint project of the San Francisco Chamber of Commerce, the trolley festival route went from the Transbay Terminal at First and Mission Streets to Market, then up the retained Market Street tracks to Duboce Avenue. From there, it followed a temporary streetcar detour built in the 1970s to bypass subway construction under Market, Duboce, Church Street, the Trolley Festival proved so successful it was repeated every year until 1987. In that year, preparation began for the introduction of a permanent F line, after that year’s festival finished, Muni replaced the old Market Street tracks with new ones, restoring tracks to upper Market Street and recreating a line to Castro. Different types of streetcars were evaluated to provide the backbone of the F-line fleet, resulting in the decision to use the PCC car. Fourteen such cars were acquired second-hand from Philadelphia to add to three of Muni’s own retired double-ended PCCs, at that point in history, this was a rare instance in which a streetcar replaced a bus line in operation, rather than the other way around. Ridership exceeded expectation, and the need for extra cars resulted in the acquisition of ten Peter Witt style cars just being retired in the city of Milan, Italy. These cars were built in the 1920s to a once common in North American cities. The Embarcadero is the eastern waterfront roadway of San Francisco, along San Francisco Bay, at one time busy with port and ferry related traffic, it fell into decline as freight transferred to the container terminals of Oakland and the Bay Bridge replaced the ferries
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Tram
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A tram is a rail vehicle which runs on tracks along public urban streets, and also sometimes on a segregated right of way. The lines or networks operated by tramcars are called tramways, Tramways powered by electricity, the most common type historically, were once called electric street railways. However, trams were used in urban areas before the universal adoption of electrification. Tram lines may run between cities and/or towns, and/or partially grade-separated even in the cities. Very occasionally, trams also carry freight, Tram vehicles are usually lighter and shorter than conventional trains and rapid transit trains, but the size of trams is rapidly increasing. Some trams may also run on railway tracks, a tramway may be upgraded to a light rail or a rapid transit line. For all these reasons, the differences between the modes of rail transportation are often indistinct. In the United States, the tram has sometimes been used for rubber-tired trackless trains. Today, most trams use electrical power, usually fed by a pantograph, in some cases by a sliding shoe on a third rail. If necessary, they may have dual power systems — electricity in city streets, trams are now included in the wider term light rail, which also includes segregated systems. The English terms tram and tramway are derived from the Scots word tram, referring respectively to a type of truck used in coal mines and the tracks on which they ran. The word tram probably derived from Middle Flemish trame, a Romanesque word meaning the beam or shaft of a barrow or sledge, the identical word la trame with the meaning crossbeam is also used in the French language. The word Tram-car is attested from 1873, although the terms tram and tramway have been adopted by many languages, they are not used universally in English, North Americans prefer streetcar, trolley, or trolleycar. The term streetcar is first recorded in 1840, and originally referred to horsecars, when electrification came, Americans began to speak of trolleycars or later, trolleys. The troller design frequently fell off the wires, and was replaced by other more reliable devices. The terms trolley pole and trolley wheel both derive from the troller, Modern trams often have an overhead pantograph mechanical linkage to connect to power, abandoning the trolley pole altogether. Conventional diesel tourist buses decorated to look like streetcars are sometimes called trolleys in the US, the term may also apply to an aerial ropeway, e. g. the Roosevelt Island Tramway. Over time, the trolley has fallen into informal use
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Twin Peaks Tunnel
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The Twin Peaks Tunnel is a 2. 27-mile -long light rail/streetcar tunnel in San Francisco, California. The tunnel runs under the Twin Peaks and is used by the K Ingleside, L Taraval, M Ocean View, the S Castro Shuttle also uses the tunnel for AT&T Park game day runs. The tunnel was opened on February 3,1918, there are two stations along the tunnel, Forest Hill Station, near the western end, and the now disused Eureka Station, near the eastern end. When the Muni Metro system and Market Street Subway were built, they were connected to the Twin Peaks Tunnel to be used by the K Ingleside, L Taraval, the Eureka Station was closed, and the Metro lines stop at the nearby Castro Street Station instead. Instead, trains continue directly from the Market Street Subway into the tunnel without going above ground, west Portal Station, which was originally a surface stop outside of the tunnels western entrance, was rebuilt as a high-platform station located just inside of the entrance. Sunset Tunnel Silent film by SF real estate company of construction of tunnel
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Sunset Tunnel
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The Sunset Tunnel is a 4,232 ft -long light rail/streetcar tunnel in San Francisco, California. The tunnel runs under the hill adjacent to Buena Vista Park and is used exclusively by the N Judah Muni Metro line. The tunnel was opened on 21 October 1928 in a ceremony presided over by Mayor James Rolph, access to the tunnel is restricted to San Francisco Municipal Railway light rail trains only. Despite the access limitations, this tunnel is not well protected, from time to time, automobile drivers manage to drive their cars into the tunnel
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