A toll road known as a turnpike or tollway, is a public or private road for which a fee is assessed for passage. It is a form of road pricing implemented to help recoup the cost of road construction and maintenance. Toll roads have existed in some form since antiquity, with tolls levied on passing travellers on foot, wagon, or horseback; the amount of the toll varies by vehicle type, weight, or number of axles, with freight trucks charged higher rates than cars. Tolls are collected at toll booths, toll houses, stations, bars, or gates; some toll collection points are unmanned and the user deposits money in a machine which opens the gate once the correct toll has been paid. To cut costs and minimise time delay many tolls are collected by some form of automatic or electronic toll collection equipment which communicates electronically with a toll payer's transponder; some electronic toll roads maintain a system of toll booths so people without transponders can still pay the toll, but many newer roads now use automatic number plate recognition to charge drivers who use the road without a transponder, some older toll roads are being upgraded with such systems.
Criticisms of toll roads include the time taken to stop and pay the toll, the cost of the toll booth operators—up to about one-third of revenue in some cases. Automated toll-paying systems help minimise both of these. Others object to paying "twice" for the same road: with tolls. In addition to toll roads, toll bridges and toll tunnels are used by public authorities to generate funds to repay the cost of building the structures; some tolls are set aside to pay for future maintenance or enhancement of infrastructure, or are applied as a general fund by local governments, not being earmarked for transport facilities. This is sometimes prohibited by central government legislation. Road congestion pricing schemes have been implemented in a limited number of urban areas as a transportation demand management tool to try to reduce traffic congestion and air pollution. Toll roads have existed for at least the last 2,700 years, as tolls had to be paid by travellers using the Susa–Babylon highway under the regime of Ashurbanipal, who reigned in the 7th century BC.
Aristotle and Pliny refer to other parts of Asia. In India, before the 4th century BC, the Arthashastra notes the use of tolls. Germanic tribes charged tolls to travellers across mountain passes. A 14th-century example is Castle Loevestein in the Netherlands, built at a strategic point where two rivers meet. River tolls were charged on boats sailing along the river; the Øresund in Scandinavia was once subject to a toll to the Danish Monarch, who derived a sizable portion of his revenue from it. Many modern European roads were constructed as toll roads in order to recoup the costs of construction, maintenance and as a source of tax money, paid by someone other than the local residents. In 14th-century England, some of the most used roads were repaired with money raised from tolls by pavage grants. Widespread toll roads sometimes restricted traffic so much, by their high tolls, that they interfered with trade and cheap transportation needed to alleviate local famines or shortages. Tolls were used in the Holy Roman Empire in the 15th centuries.
Industrialisation in Europe needed major improvements to the transport infrastructure which included many new or improved roads, financed from tolls. The A5 road in Britain was built to provide a robust transport link between Britain and Ireland and had a toll house every few miles. In the 20th century, road tolls were introduced in Europe to finance the construction of motorway networks and specific transport infrastructure such as bridges and tunnels. Italy was the first European country to charge motorway tolls, on a 50 kilometres motorway section near Milan in 1924, it was followed by Greece, which made users pay for the network of motorways around and between its cities in 1927. In the 1950s and 1960s, France and Portugal started to build motorways with the aid of concessions, allowing rapid development of this infrastructure without massive state debts. Since road tolls have been introduced in the majority of the EU member states. In the United States, prior to the introduction of the Interstate Highway System and the large federal grants supplied to states to build it, many states constructed their first controlled-access highways by floating bonds backed by toll revenues.
Starting with the Pennsylvania Turnpike in 1940, followed by similar roads in New Jersey, New York and others, numerous states throughout the 1950s established major toll roads. With the establishment of the Interstate Highway System in the late 1950s, toll road construction in the U. S. slowed down as the federal government now provided the bulk of funding to construct new freeways, regulations required that such Interstate highways be free from tolls. Many older toll roads were added to the Interstate System under a grandfather clause that allowed tolls to continue to be collected on toll roads that predated the system; some of these such as the Connecticut Turnpike and the Richmond–Petersburg Turnpike removed their tolls when the initial bonds were paid off. Many states, have maintained the tolling of these roads as a consistent source of revenue; as the
Yachting refers to the use of recreational boats and ships called yachts for sporting purposes. Yachts are distinguished from working ships by their leisure purpose. Both terms originate from the Dutch word jacht. With sailboats, it is called sailing, with motorboats, it is called powerboating; the invention of sailing is prehistoric, but the racing of sailing boats is believed to have started in the Netherlands some time in the 17th century. Soon, in England, custom-built racing "yachts" began to emerge. In 1851, the Royal Yacht Squadron in Cowes challenged the American yacht America; the race took place in the Solent. The America won the race and took the trophy, the America's Cup, back to the US where, held by the New York Yacht Club, it remained until 1983; the cup was lost to the Royal Perth Yacht Club of Australia, which entered the Australia II into the contest. Meanwhile, yacht racing continued to evolve, with the development of recognised classes of racing yachts, from small dinghies up to huge maxi yachts.
Although there are many different types of racing vessels, they can be separated into the larger yachts, which are larger and contain facilities for extended voyages, smaller harbour racing craft such as dinghies and skiffs. Smaller boats are not referred to as yachts, although all recreational boats are yachts; these days, yacht racing and dinghy racing are common participant sports around the developed world where favorable wind conditions and access to reasonably sized bodies of water are available. Most yachting is conducted in salt water, but smaller craft can be raced on lakes and large rivers. Dinghy races are conducted on sheltered water on smaller craft with crews of between one and three people; the common arrangement for racing boats is a boat with one mast. Some dinghies have only one triangular sail. Most races are conducted between vessels of identical design. In these races, with identical equipment the sailors best able to make use of the ambient conditions win. Dinghy designs vary from small and slow craft for novice sailors to lightweight, high-speed designs that are difficult for experienced crews to sail safely and effectively.
Australia's 18-foot skiff class are the fastest monohull dinghies, reaching speeds of up to 40 kilometres per hour in light winds. Sailing has a reputation for being a boring spectator sport, but skiff racing can be exciting in unpredictable conditions where crews struggle to keep their boats upright. Various multi-hull racing classes are faster. Various one-design dinghy classes are raced at the Summer Olympic Games. Larger yachts are raced on harbours, but the most prestigious yacht races are point-to-point long distance races on the open ocean. Bad weather makes finishing such races a considerable test of equipment and willpower, from time to time boats and sailors are lost at sea; the longest such events are "round-the-world" races which can take months to complete, but better-known are events such as the Fastnet race in the United Kingdom and the Sydney to Hobart Yacht Race along the east coast of Australia. Large races are organized with a first-past-the-post trophy and under a handicap system that adjusts finishing times for the relative speeds of the boats' design, theoretically offering each entrant an equal chance.
While sailing groups organize the most active and popular competitive yachting, other boating events are held worldwide: speed motor boat racing. Specialized yachts, such as hydrofoils, hovercrafts, or personal watercrafts engage in competitions involving test of equipment and skill. All such events are part of the larger world of yachting, if they are done for recreational or sporting purposes. Common commercial uses of watercraft, which would not be referred to as yachting, include commercial fishing, operation of ferries, military applications. In these cases, larger vessels are referred to as ships, smaller vessels as either ships or boats, although boat is a generic term that could be applied to a recreational yacht or a commercial or military vessel of smaller size. Cruising involves traveling on a boat, whether across a bay, on the Great Lakes or from island to island in the South Pacific. Safe cruising across long distances requires a degree of self-sufficiency and a wide range of skills beyond handling the boat.
Knowledge of topics such as navigation, meteorology and electrical systems, first aid, sea survival and more are needed and can be life saving when cruising to distant shores. In the US, the United States Power Squadrons offer certifications in these skills. In the UK, a system of certification is run by the Royal Yachting Association. Similar systems are offered by organizations in other countries and include a range of courses, both theoretical and practical. Boating Classic Boat Museum Cruising Dinghy racing Dinghy sailing Luxury yacht Sailing Yacht charter Yacht club Yacht racing Media related to Yachting at Wikimedia Commons
Interstate 275 (Florida)
Interstate 275, located in Florida, is a 60-mile-long highway serving the Tampa Bay Area. Its southern terminus is at Interstate 75 near Palmetto, where I-275 heads west towards the Sunshine Skyway Bridge crossing over Tampa Bay. From that point, I-275 passes through St. Petersburg before crossing Tampa Bay again on the Howard Frankland Bridge continues through the city of Tampa, where it connects to an interchange with Interstate 4 in Downtown Tampa. After the interchange, I-275 passes north through the Tampa suburbs to its northern terminus at Interstate 75 in Wesley Chapel. Interstate 275 and its parent route Interstate 75 follow the opposite of the usual conventions of freeway routing; the parent route runs through a metropolitan area while an interstate with a three-digit number serves as the bypass route. However, in this case I-275 runs through Tampa and St. Petersburg, while I-75 serves as the bypass route. Interstate 275 begins at exit 228 of Interstate 75 with two lanes in either direction in rural Palmetto.
275 heads west of its parent interstate and has an interchange US 41 2 miles up the road. I-275's next interchange is beginning a concurrency that lasts 13 miles. After this exit, I-275 reaches the Southern toll plaza for the Sunshine Skyway Bridge. There is a corresponding Northern toll plaza for southbound travelers; the Sunshine Skyway Bridge is a 4.1-mile-long bridge. After reaching the northern end of the bridge, 275 enters St. Petersburg. At the northern end of the bridge, drivers drive on the left side as the freeway's lanes invert for about half a mile before US 19 exits the freeway, serving as a local road in St. Petersburg. I-275 has multiple exits in the city, each of them serving the residential neighborhoods that the freeway passes through. At this point, the interstate widens to 3 lanes in either direction. 275's next major interchange is with Interstate 175, which provides access to Albert Whitted Airport and Tropicana Field, home of the Tampa Bay Rays. The next major interchange occurs less than a mile down the road with Interstate 375, providing access to the waterfront along Tampa Bay.
After this exit, I-275 continues through residential neighborhoods until it passes beside Sawgrass Lake Park and through an area of marshland. The freeway widens to four lanes in either direction before reaching its last interchange in St. Petersburg with SR 687. After traveling 19 miles in St. Petersburg, I-275 crosses the Howard Frankland Bridge over Old Tampa Bay into Tampa. I-275 has an interchange with SR 589, allowing access to Tampa International Airport. At this point, I-275 thins down to three lanes in either direction, remains this way for the rest of the freeway. 275 has an interchange with US 92, the first of two interchanges with the road, allowing access to downtown Tampa. 275 crosses the Hillsborough River for the first time along its route. Afterwards, 6 miles from its entry into Tampa, I-275 has its next major interchange with Interstate 4, a junction known locally as Malfunction Junction; this junction was subsequently overhauled. This interchange serves as I-4's western terminus, allows access to Orlando and the east coast of Florida.
After this major exit, 275 reaches an interchange with US 92 again allowing access to US 41. After this interchange, US 41 acts as the local road for the freeway for the rest of its route. 275 enters residential neighborhoods within Tampa. 275 travels due north and parallel to US 41 for 4 miles before turning northeast towards Interstate 75. At this point, 275 exits enters Lutz, a suburb of Tampa. I-275 reconnects with its parent interstate highway and reaches its northern terminus. Between southern terminus and Exit 17: two lanes each way excluding the toll plaza Between Exit 17 and Exit 30: three lanes each way Between Exits 22 and 23A: two lanes each way Between Exits 25 and 26: four lanes each way, with the right lane in both directions designated "exit only" Between Exits 30 and 39, including the Howard Frankland Bridge: four lanes each way Between Exit 39 and northern terminus: three lanes each way Through Exit 39 two lanes in each way Southbound I-275 two lanes for most I-275 I-4 interchange I-275 opened in 1962 as a segment of I-75, from the present northern terminus to a diamond interchange at Bearss Avenue.
The portion of Interstate 4 that would become a part of I-275, the Howard Frankland Bridge, its short freeway stubs at the bridge's endpoints, opened to traffic about a year earlier. In 1964, the stub of what was known as I-4 between 50th St. and Armenia Avenue was completed. "Malfunction Junction's" northern end was a pair of ramp stubs that would be filled in by I-75. In 1965, the segment of I-75 from "Malfunction Junction" to about Sligh Avenue was completed, by 1967, the remaining gaps in I-4 and I-75 were filled and opened to traffic. Around 1970, plans for the extension of I-75 into Pinellas County began. However, the first round of local opposition would lead to the eventual delays of I-75 through St. Petersburg; the first setback was led by 4th Street business owners and residents who demanded that construction on I-75 be stopped, since the bridge was funneling unwanted traffic into the corridor. It has since seen many unforeseen business and residential booms, due to the building of this bridge.
At the same time, construction began on I-75 from Roosevelt Boulevard to about 38th Avenue North. By this time, I-4 was truncated to "Malfunction Junction," allowing the I-75 designa
U.S. Route 19 in Florida
U. S. Route 19 in Florida runs 264 miles along Florida's west coast from an interchange with U. S. Route 41 in Memphis, south of Tampa, continues to the Georgia border north of Monticello, Florida; as is the case with all Florida roads with federal designations, the entirety of US 19 has a hidden Florida Department of Transportation designation: State Road 55 from the US route's southern terminus at US 41 south of Terra Ceia to the junction with US 221 / SR 55 north in Perry. State Road 30 from the junction with US 221 / SR 55 in Perry for one mile to the junction with US 27 south / US 98 west via US 221 Truck. State Road 20 from the junction with US 27/US 98 in Perry cosigning with US 27 until the routes split in Capps. State Road 57 from the US 27/SR 20 split in Capps to the Georgia state line north of Texas Hill. US 19 remains independent of I-75 as the routes converge in the Tampa Bay Area; the route is co-signed with Interstate 275 over the Sunshine Skyway Bridge, a cable-stayed bridge over the mouth of Tampa Bay, US 98 between Chassahowitzka and Perry, Alternate US 27 between Chiefland and Perry, US 27 between and Perry and Capps.
The road begins at an interchange with U. S. Route 41 in Manatee County, remains independent until the interchange with Interstate 275 at Exit 5, where it overlaps I-275 across the Sunshine Skyway Bridge, the terminus of, at Interstate 275 & State Road 682 at Exit 17. According to a Dateline NBC study, part of US 19 in Florida is the most dangerous road in the United States. A Florida Highway Patrol test period beginning in 1998 and ending in 2003, as mandated by the National Highway Traffic Safety Administration, showed the stretch of US 19 from Pasco County to Pinellas County to average 52 deaths a year, or 262 deaths in the 5-year duration of the study. 100 of these deaths were pedestrian related making US 19 the #1 worst road to walk on in these two counties. Multiple efforts to improve US 19 have been suggested to the FDOT. Within Downtown St. Petersburg, US 19 crosses Alternate US 19, which used to serve as the southern terminus of Alt US 19 until 2006. US 19 runs along 34th Street until just south of the interchange at State Road 694 at Gandy and Park Boulevards in Pinellas Park.
This interchange was intended for the proposed Gandy Freeway. In eastern Largo, State Road 688 shares an interchange with the northern terminus of State Road 693, a road that leads to St. Pete Beach and was once part of State Road A19A. After this, the next interchange is at State Road 686, the road to the St. Petersburg-Clearwater Airport. State Road 60 is the site of the world's first Single-point urban interchange. Drew Street is north of the interchange, for years has been a source of major accidents. By 2006, the freeway gap was filled between SR 60 and Sunset Point Boulevard, however the service roads terminate at a creek between Drew Street and Coachman Road, creating a traffic situation similar to that of the Oakdale Merge on Long Island, New York; as of 2017, US 19 is built to freeway standards from just south of 49th Street N to just north of State Road 580. The freeway is built in the style of many Texas freeways, with service roads along the length of the route and Texas u-turns at major interchanges.
When Alternate US 19 terminates at US 19 in Holiday across from a major trailer park, a de facto extension of the road serves as a brief multiplex with US 19 in Holiday which terminates a block north of the northern terminus of Alternate US 19 in Holiday at Mile Stretch Road. After the intersection with Moog Road, US 19 takes a slight curve to the northeast before intersecting with State Road 54. Shortly after this, the road crosses CR 518 dips as it approaches the gateway to Gulf Harbors and curves straight north before reaching Gulf Boulevard. Downtown New Port Richey can be found two miles north of this point at Main Street, the northern terminus of unamrked southern CR 595, although the terminus used to be at Grand Boulevard in Port Richey; the bridge over the Pithlachascotee River, which carries US 19 from New Port Richey to Port Richey was a two-lane drawbridge until 1965. An older version of that bridge is now fishing pier owned by a boat rental dealership. Just as in Pinellas County, US 19 in Pasco County has been rated the most dangerous road in the United States.
Ridge Road is considered to be one of the most dangerous intersection of US 19. However instead of making any genuine effort to improve the intersection by building an interchange, local governments have allowed developers to add a Wal-Mart and smaller stores in the vicinity of the intersection; the closest thing to an interchange, considered is an overpass for left-turn lanes. North of Ridge Road, US 19 passes by the Gulf View Square Mall as well as the Embassy Plaza and Embassy Crossing shopping centers on the oppostite side of the mall. North of these two shopping centers, a marginal dirt road can be found on the east side of US 19 as far north as Fox Hollow Drive, while on the west side a paved road that may have been part of the old US 19 runs from the north end of the mall to Clemens Boulevard. After this, the road intersects CR 77 south of Jasmine Estates, only noticed because an 18 screen movie theater is located opposite from the terminus, before turning straight north again near the intersection with Hammock Road and Ranch Road.
The next major intersection is State Road 52 in Bayonet Point. The southwest corner of SR 52 is dominated by a flea market, a race track. After curving from north to northeast near the Old Dixie Highway in Hudson Beach, US 19 intersects with Hudson Avenue and Fivay Drive, the latter of, par
Boca Ciega Bay
Boca Ciega Bay is a body of water bordering Gulfport, Florida, St. Petersburg, other municipalities in Pinellas County. Clam Bayou estuary feeds into the bay. Boca Ciega Bay is an aquatic preserve designated in 1968 to halt dredging-and-filling work done in the 1950s. There are mangrove islands as well as miles of canals bounded by seawalls. Along with the Pinellas County Aquatic Preserve, Boca Ciega Bay provides sandy beaches, mangrove shoreline and submerged habitats such as oyster bars, seagrass beds, coral habitat, spring-fed caves; the 185-acre Boca Ciega Millennium Park in Seminole, Florida, is a protected natural area and preserve. The park features a 35-foot wooden observation tower with a panoramic view of Boca Ciega Bay; the park is a stop on the Florida Fish and Wildlife Conservation Commission's "Great Florida Birding Trail." Intracoastal Waterway
Pinellas County, Florida
Pinellas County is a county located in the state of Florida. As of the 2010 census, the population was 916,542; the county is part of the Tampa–St. Petersburg–Clearwater, Florida Metropolitan Statistical Area. Clearwater is the county seat, St. Petersburg is the largest city. Prior to European exploration and settlement the Pinellas peninsula, like all of Tampa Bay, was inhabited by the Tocobaga Indians, who built a town and large temple mound overlooking the bay in what is now Safety Harbor; the modern site can be visited as part of the County's Philippe Park. During the early 16th century Spanish explorers discovered and began exploring Florida, including Tampa Bay. In 1528 Panfilo de Narvaez landed in Pinellas, 10 years Hernando de Soto is thought to have explored the Tampa Bay Area. By the early 18th century the Tocobaga had been annihilated, having fallen victim to European diseases from which they had no immunity, as well as European conflicts. Spanish explorers named the area Punta Piñal.
After trading hands multiple times between the British and the Spanish, Spain ceded Florida to the United States in 1821, in 1823 the U. S. Army established Fort Brooke. In 1834 much of west central Florida, including the Pinellas peninsula, was organized as Hillsborough County; the next year Odet Philippe became the first permanent, non-native resident of the peninsula when he established a homestead near the site of the Tocobaga village in Safety Harbor. It was Philippe who first introduced both citrus cigar-making to Florida. Around the same time, the United States Army began construction of Fort Harrison, named after William Henry Harrison, as a rest post for soldiers from nearby Fort Brooke during the Second Seminole War; the new fort was located on a bluff overlooking Clear Water Harbor, which became part of an early 20th-century residential development called Harbor Oaks. University of South Florida archaeologists excavated the site in 1977 after Alfred C. Wyllie discovered an underground ammunition bunker.
Clearwater would become the first organized community on the peninsula as well as the site of its first post office. The Armed Occupation Act, passed in 1842, encouraged further settlement of Pinellas, like all of Florida, by offering 160 acres to anyone who would bear arms and cultivate the land. Pioneer families like the Booths, the Coachmans, the Marstons, the McMullens established homesteads in the area in the years following, planting more citrus groves and raising cattle. During the American Civil War, many residents fought for the Confederate States of America. Brothers James and Daniel McMullen were members of the Confederate Cow Cavalry, driving Florida cattle to Georgia and the Carolinas to help sustain the war effort. John W. Marston served in the 9th Florida Regiment as a part of the Appomattox Campaign. Many other residents served in other capacities. Otherwise the peninsula had no significance during the war, the war passed the area by. Tarpon Springs became West Hillsborough's first incorporated city in 1887, in 1888 the Orange Belt Railway was extended into the southern portion of the peninsula.
Railroad owner Peter Demens named the town that grew near the railroad's terminus St. Petersburg in honor of his hometown; the town would incorporate in 1892. Other major towns in the county incorporated during this time were Clearwater and Largo. Construction of Fort De Soto, on Mullet Key facing the mouth of Tampa Bay, was begun in 1898 during the Spanish–American War to protect Tampa Bay from potential invading forces; the fort, a subpost of Fort Dade on adjacent Egmont Key, was equipped with artillery and mortar batteries. Into the early years of the 20th century, West Hillsborough had no paved roads, transportation posed a major challenge. A trip to the county seat, across the bay in Tampa, was an overnight affair and the automobiles that existed on the peninsula at that time would become bogged down in the muck after rainstorms. Angry at what was perceived as neglect by the county government, residents of Pinellas began a push to secede from Hillsborough, they succeeded, on January 1, 1912 Pinellas County came into being.
The peninsula, along with a small part of the mainland were incorporated into the new county. Aviation history was made in St. Petersburg on January 1, 1914 when Tony Jannus made the world's first scheduled commercial airline flight with the St. Petersburg-Tampa Airboat Line from St. Petersburg to Tampa; the popular open-air St. Petersburg concert venue Jannus Live memorializes the flight; the early 1920s saw the beginning of a land boom including Pinellas. During this period municipalities issued a large number of bonds to keep pace with the needed infrastructure, such as roads and bridges; the travel time to Tampa was cut in half—from 43 to 19 miles —by the opening of the Gandy Bridge in 1924, along the same route Jannus' airline used. It was the longest automobile toll bridge in the world at the time. Prohibition was unpopular in the area and the peninsula's countless inlets and islands became havens for rumrunners bringing in liquor from Cuba. Others distilled moonshine in the County's still plentiful woods.
As was the case in much of Florida, the Great Depression came early to Pinellas with the collapse of the real estate boom in 1926. Local economies came into severe difficulties, by 1930, St. Petersburg defaulted on its bonds. Only after World War II would significant growth
A causeway is a track, road or railway on top of an embankment across "a low, or wet place, or piece of water". It can be constructed of earth, wood, or concrete. One of the earliest known wooden causeways is the Sweet Track in the Somerset Levels, that dates from the Neolithic age. Timber causeways may be described as both boardwalks and bridges; when first used, the word appeared in a form such as "causey way" making clear its derivation from the earlier form "causey". This word seems to have come from the same source by two different routes, it derives from the Latin for heel and most comes from the trampling technique to consolidate earthworks. The construction of a causeway utilised earth, trodden upon to compact and harden it as much as possible, one layer at a time by slaves or flocks of sheep. Today, this work is done by machines; the same technique would have been used for road embankments, raised river banks, sea banks and fortification earthworks. The second derivation route is the hard, trodden surface of a path.
The name by this route came to be applied to a firmly-surfaced road. It is now little-used except in dialect and in the names of roads which were notable for their solidly-made surface; the 1911 Encyclopædia Britannica states "causey, a mound or dam, derived, through the Norman-French caucie, from the late Latin via calciata, a road stamped firm with the feet."The word is comparable in both meanings with the French chaussée, from a form of which it reached English by way of Norman French. The French adjective, chaussée, carries the meaning of having been given a hardened surface, is used to mean either paved or shod; as a noun chaussée is used on the one hand for a metalled carriageway, on the other for an embankment with or without a road. Other languages have a noun with similar dual meaning. In Welsh, it is sarn; the Welsh is relevant here, as it has a verb, meaning to trample. The trampling and ramming technique for consolidating earthworks was used in fortifications and there is a comparable, outmoded form of wall construction technique, used in such work and known as pisé, a word derived not from trampling but from ramming or tamping.
The Welsh word'cawsai' translates directly to the English word'causeway'. A transport corridor, carried instead on a series of arches approaching a bridge, is a viaduct; the distinction between the terms causeway and viaduct becomes blurred when flood-relief culverts are incorporated, though a causeway refers to a roadway supported by earth or stone, while a bridge supports a roadway between piers. Some low causeways across shore waters become inaccessible; the Aztec city-state of Tenochtitlan had causeways supporting aqueducts. One of the oldest engineered roads yet discovered is the Sweet Track in England. Built in 3807 or 3806 BC, the track was a walkway consisting of planks of oak laid end-to-end, supported by crossed pegs of ash and lime, driven into the underlying peat; the modern embankment may be constructed within a cofferdam: two parallel steel sheet pile or concrete retaining walls, anchored to each other with steel cables or rods. This construction may serve as a dyke that keeps two bodies of water apart, such as bodies with a different water level on each side, or with salt water on one side and fresh water on the other.
This may be the primary purpose of a structure, the road providing a hardened crest for the dike, slowing erosion in the event of an overflow. It provides access for maintenance as well as a public service. Notable causeways include those that connect Singapore and Malaysia and Saudi Arabia and Venice to the mainland, all of which carry roadways and railways. In the Netherlands there are a number of prominent dikes which double as causeways, including the Afsluitdijk and Markerwaarddijk. In Louisiana, two long bridges, called the Lake Pontchartrain Causeway, stretch across Lake Pontchartrain for 38 km, making them the world's longest bridges, they are the oldest causeways on the Gulf Coast that have never been put out of commission for an extended period of time following a Hurricane. In the Republic of Panama a causeway connects the islands of Perico and Naos to Panama City on the mainland, it serves as a breakwater for ships entering the Panama Canal. Causeways are common in Florida, where low bridges may connect several man-made islands with a much higher bridge in the middle so that taller boats may pass underneath safely.
Causeways are most used to connect the barrier islands with the mainland. The Churchill Barriers in Orkney are of the most notable sets of causeways in Europe. Constructed in waters up to 18 metres deep, the four barriers link five islands on the eastern side of the natural harbour at Scapa Flow, they were built during World War II as military defences for the harbour, on the orders of Winston Churchill. The Estrada do Istmo connecting the islands of Taipa and Coloane in Macau was built as a causeway; the sea on both sides of the causeway became shallower as a result of silting, mangroves began to conquer the area. Land reclamation took place on both sides of the road and the area has subsequently been named Cotai and b