Human prehistory is the period between the use of the first stone tools c. 3.3 million years ago by hominins and the invention of writing systems. The earliest writing systems appeared c. 5,300 years ago, but it took thousands of years for writing to be adopted, it was not used in some human cultures until the 19th century or until the present. The end of prehistory therefore came at different dates in different places, the term is less used in discussing societies where prehistory ended recently. Sumer in Mesopotamia, the Indus valley civilization, ancient Egypt were the first civilizations to develop their own scripts and to keep historical records. Neighboring civilizations were the first to follow. Most other civilizations reached the end of prehistory during the Iron Age; the three-age system of division of prehistory into the Stone Age, followed by the Bronze Age and Iron Age, remains in use for much of Eurasia and North Africa, but is not used in those parts of the world where the working of hard metals arrived abruptly with contact with Eurasian cultures, such as the Americas, Oceania and much of Sub-Saharan Africa.
These areas with some exceptions in Pre-Columbian civilizations in the Americas, did not develop complex writing systems before the arrival of Eurasians, their prehistory reaches into recent periods. The period when a culture is written about by others, but has not developed its own writing is known as the protohistory of the culture. By definition, there are no written records from human prehistory, so dating of prehistoric materials is crucial. Clear techniques for dating were not well-developed until the 19th century; this article is concerned with human prehistory, the time since behaviorally and anatomically modern humans first appeared until the beginning of recorded history. Earlier periods are called "prehistoric". Beginning The term "prehistory" can refer to the vast span of time since the beginning of the Universe or the Earth, but more it refers to the period since life appeared on Earth, or more to the time since human-like beings appeared. End The date marking the end of prehistory is defined as the advent of the contemporary written historical record.
The date varies from region to region depending on the date when relevant records become a useful academic resource. For example, in Egypt it is accepted that prehistory ended around 3200 BCE, whereas in New Guinea the end of the prehistoric era is set much more at around 1900 common era. In Europe the well-documented classical cultures of Ancient Greece and Ancient Rome had neighbouring cultures, including the Celts and to a lesser extent the Etruscans, with little or no writing, historians must decide how much weight to give to the highly prejudiced accounts of these "prehistoric" cultures in Greek and Roman literature. Time periods In dividing up human prehistory in Eurasia, historians use the three-age system, whereas scholars of pre-human time periods use the well-defined geologic record and its internationally defined stratum base within the geologic time scale; the three-age system is the periodization of human prehistory into three consecutive time periods, named for their respective predominant tool-making technologies: Stone Age Bronze Age Iron Age The notion of "prehistory" began to surface during the Enlightenment in the work of antiquarians who used the word'primitive' to describe societies that existed before written records.
The first use of the word prehistory in English, occurred in the Foreign Quarterly Review in 1836. The use of the geologic time scale for pre-human time periods, of the three-age system for human prehistory, is a system that emerged during the late nineteenth century in the work of British and Scandinavian archeologists and anthropologists; the main source for prehistory is archaeology, but some scholars are beginning to make more use of evidence from the natural and social sciences. This view has been articulated by advocates of deep history; the primary researchers into human prehistory are archaeologists and physical anthropologists who use excavation and geographic surveys, other scientific analysis to reveal and interpret the nature and behavior of pre-literate and non-literate peoples. Human population geneticists and historical linguists are providing valuable insight for these questions. Cultural anthropologists help provide context for societal interactions, by which objects of human origin pass among people, allowing an analysis of any article that arises in a human prehistoric context.
Therefore, data about prehistory is provided by a wide variety of natural and social sciences, such as paleontology, archaeology, geology, comparative linguistics, molecular genetics and many others. Human prehistory differs from history not only in terms of its chronology but in the way it deals with the activities of archaeological cultures rather than named nations or individuals. Restricted to material processes and artifacts rather than written records, prehistory is anonymous; because of this, reference terms that prehistorians use, such as Neanderthal or Iron Age are modern labels with definitions sometimes subject to debate. The concept of a "Stone Age" is found useful in the archaeology of most of the world, though in the archaeology of the Americas it is called by different names and begins with a Lithic sta
Lapis lazuli, or lapis for short, is a deep blue metamorphic rock used as a semi-precious stone, prized since antiquity for its intense color. As early as the 7th millennium BCE, lapis lazuli was mined in the Sar-i Sang mines, in Shortugai, in other mines in Badakhshan province in northeast Afghanistan. Lapis was valued by the Indus Valley Civilisation. Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, as far from Afghanistan as Mauritania, it was used in the funeral mask of Tutankhamun. At the end of the Middle Ages, lapis lazuli began to be exported to Europe, where it was ground into powder and made into ultramarine, the finest and most expensive of all blue pigments, it was used by some of the most important artists of the Renaissance and Baroque, including Masaccio, Perugino and Vermeer, was reserved for the clothing of the central figures of their paintings the Virgin Mary. Today, mines in northeast Afghanistan are still the major source of lapis lazuli. Important amounts are produced from mines west of Lake Baikal in Russia, in the Andes mountains in Chile.
Smaller quantities are mined in Italy, the United States, Canada. Lapis is the Latin word for "stone" and lazulī is the genitive form of the Medieval Latin lazulum, taken from the Arabic لازورد lāzaward, itself from the Persian لاجورد lājevard, the name of the stone in Persian and of a place where lapis lazuli was mined. "Lazulum" is etymologically related to the color blue and used as a root for the word for blue in several languages, including Spanish and Portuguese "azul". The most important mineral component of lapis lazuli is lazurite, a feldspathoid silicate mineral with the formula 861-2. Most lapis lazuli contains calcite and pyrite; some samples of lapis lazuli contain augite. Lapis lazuli occurs in crystalline marble as a result of contact metamorphism; the intense blue color is due to the presence of the trisulfur radical anion in the crystal. An electronic excitation of one electron from the highest doubly filled molecular orbital into the lowest singly occupied orbital results in a intense absorption line at λmax ~617 nm.
Lapis lazuli is found in limestone in the Kokcha River valley of Badakhshan province in northeastern Afghanistan, where the Sar-e-Sang mine deposits have been worked for more than 6,000 years. Afghanistan was the source of lapis for the ancient Egyptian and Mesopotamian civilizations, as well as the Greeks and Romans. Ancient Egyptians obtained this material through trade from Afghanistan with the Aryans. During the height of the Indus Valley Civilisation about 2000 BCE, the Harappan colony now known as Shortugai was established near the lapis mines. According to the Sorbonne's mineralogist Pierre Bariand's leading work on the sources of lapis lazuli in modern times, to references in Afghanistan's Blue Treasure: Lapis Lazuli by Lailee McNair Bakhtiar, the lapis lazuli is found in "caves" not traditionally considered "mines" and the stone lapis lazuli is from the primary source of the Hindu Kush Mountains in Afghanistan's Kochka River Valley and not in Pakistan. In addition to the Afghan deposits, lapis is extracted in the Andes.
It is mined in smaller amounts in Angola. Lapis takes an excellent polish and can be made into jewelry, boxes, ornaments, small statues, vases. During the Renaissance, Lapis was ground and processed to make the pigment ultramarine for use in frescoes and oil painting, its usage as a pigment in oil paint ended in the early 19th century when a chemically identical synthetic variety became available. Lapis lazuli is commercially synthesized or simulated by the Gilson process, used to make artificial ultramarine and hydrous zinc phosphates, it may be substituted by spinel or sodalite, or by dyed jasper or howlite. Lapis lazuli has been mined in Afghanistan and exported to the Mediterranean world and South Asia since the Neolithic age. Lapis lazuli beads have been found at Mehrgarh, a neolithic site near Quetta in Pakistan, on the ancient trade route between Afghanistan and the Indus Valley, dating to the 7th millennium BCE. Quantities of these beads have been found at 4th millennium BCE settlements in Northern Mesopotamia, at the Bronze Age site of Shahr-e Sukhteh in southeast Iran.
A dagger with a lapis handle, a bowl inlaid with lapis, amulets and inlays representing eyebrows and beards, were found in the Royal Tombs of the Sumerian city-state of Ur from the 3rd Millennium BCE. Lapis was used in ancient Mesopotamia by the Akkadians and Babylonians for seals and jewelry. In the Mesopotamian poem the Epic of Gilgamesh, one of the oldest known works of literature, lapis lazuli is mentioned several times; the Statue of Ebih-Il, a 3rd millennium BCE statue found in the ancient city-state of Mari in modern-day Syria, now in the Louvre, uses lapis lazuli inlays for the irises of the eyes. In ancient Egypt, lapis lazuli was a favorite stone for ornaments such as scarabs. Lapis jewelry has been found at excavations of the Predynastic Egyptian site Naqada. At Karnak, the relief carvings of Thutmose III show fragments and barrel-shaped pieces of lapis lazuli being delivered to him as tribute. Powdered lapis was u
Afghanistan the Islamic Republic of Afghanistan, is a landlocked country located in South-Central Asia. Afghanistan is bordered by Pakistan in the south and east, its territory covers 652,000 square kilometers and much of it is covered by the Hindu Kush mountain range, which experiences cold winters. The north consists of fertile plains, while the south-west consists of deserts where temperatures can get hot in summers. Kabul serves as its largest city. Human habitation in Afghanistan dates back to the Middle Paleolithic Era, the country's strategic location along the Silk Road connected it to the cultures of the Middle East and other parts of Asia; the land has been home to various peoples and has witnessed numerous military campaigns, including those by Alexander the Great, Muslim Arabs, British and since 2001 by the United States with NATO-allied countries. It has been called "unconquerable" and nicknamed the "graveyard of empires"; the land served as the source from which the Kushans, Samanids, Ghaznavids, Khaljis, Hotaks and others have risen to form major empires.
The political history of the modern state of Afghanistan began with the Hotak and Durrani dynasties in the 18th century. In the late 19th century, Afghanistan became a buffer state in the "Great Game" between British India and the Russian Empire, its border with British India, the Durand Line, was formed in 1893 but it is not recognized by the Afghan government and it has led to strained relations with Pakistan since the latter's independence in 1947. Following the Third Anglo-Afghan War in 1919 the country was free of foreign influence becoming a monarchy under King Amanullah, until 50 years when Zahir Shah was overthrown and a republic was established. In 1978, after a second coup Afghanistan first became a socialist state and a Soviet Union protectorate; this evoked the Soviet–Afghan War in the 1980s against mujahideen rebels. By 1996 most of Afghanistan was captured by the Islamic fundamentalist group the Taliban, who ruled most of the country as a totalitarian regime for over five years.
The Taliban were forcibly removed by the NATO-led coalition, a new democratically-elected government political structure was formed, but they still control a significant portion of the country. Afghanistan is a unitary presidential Islamic republic with a population of 31 million composed of ethnic Pashtuns, Tajiks and Uzbeks, it is a member of the United Nations, the Organisation of Islamic Cooperation, the Group of 77, the Economic Cooperation Organization, the Non-Aligned Movement. Afghanistan's economy is the world's 108th largest, with a GDP of $64.08 billion. The name Afghānistān is believed to be as old as the ethnonym Afghan, documented in the 10th-century geography book Hudud ul-'alam; the root name "Afghan" was used in reference to a member of the ethnic Pashtuns, the suffix "-stan" means "place of" in Persian. Therefore, Afghanistan translates to land of the Afghans or, more in a historical sense, to land of the Pashtuns. However, the modern Constitution of Afghanistan states that "he word Afghan shall apply to every citizen of Afghanistan."
Excavations of prehistoric sites by Louis Dupree and others suggest that humans were living in what is now Afghanistan at least 50,000 years ago, that farming communities in the area were among the earliest in the world. An important site of early historical activities, many believe that Afghanistan compares to Egypt in terms of the historical value of its archaeological sites; the country sits at a unique nexus point where numerous civilizations have interacted and fought. It has been home to various peoples through the ages, among them the ancient Iranian peoples who established the dominant role of Indo-Iranian languages in the region. At multiple points, the land has been incorporated within large regional empires, among them the Achaemenid Empire, the Macedonian Empire, the Indian Maurya Empire, the Islamic Empire. Many empires and kingdoms have risen to power in Afghanistan, such as the Greco-Bactrians, Hephthalites, Kabul Shahis, Samanids, Ghurids, Kartids, Timurids and the Hotak and Durrani dynasties that marked the political origins of the modern state.
Archaeological exploration done in the 20th century suggests that the geographical area of Afghanistan has been connected by culture and trade with its neighbors to the east and north. Artifacts typical of the Paleolithic, Neolithic and Iron ages have been found in Afghanistan. Urban civilization is believed to have begun as early as 3000 BCE, the early city of Mundigak may have been a colony of the nearby Indus Valley Civilization. More recent findings established that the Indus Valley Civilisation stretched up towards modern-day Afghanistan, making the ancient civilisation today part of Pakistan and India. In more detail, it extended from what today is northwest Pakistan to northwest India and northeast Afghanistan. An Indus Valley site has been found on the Oxus River at Shortugai in northern Afghanistan. There are several smaller IVC colonies to be found in Afghanistan as well. After 2000 BCE, successive waves of semi-nomadic
Mindat.org is a non-commercial online mineralogical database, claiming to be the largest mineral database and mineralogical reference website on the internet. It is used by amateur mineral collectors alike, it contains a significant database of minerals and mineral photographs, is updated by registered users adding and editing entries. As of 2016, it included: 45,289 mineral names, of which 5,091 are minerals or mineraloids recognized by the International Mineralogical Association. 261,955 mineral localities worldwide, with information on 903,204 mineral occurrences within these sites. Over 647,000 photos of minerals have been uploaded, arranged into galleries from collectors and institutions worldwide who wish to share their mineral collections online. 48,657 users edit data. Mindat was started in 1993 as a personal database project by Jolyon Ralph, he developed further versions as a Microsoft Windows application before launching a community-editable database web site in October 2000. Mindat.org is now part of the Hudson Institute of Mineralogy, a 501 not-for-profit educational foundation incorporated in the state of New York.
Jolyon Ralph was awarded the Mineralogical Society of America's Distinguished public service medal in 2011 for his work on Mindat.org. Mindat.org site Mindat.org - 10 years online today
National Geospatial-Intelligence Agency
The National Geospatial-Intelligence Agency is a combat support agency under the United States Department of Defense and a member of the United States Intelligence Community, with the primary mission of collecting and distributing geospatial intelligence in support of national security. NGA was known as the National Imagery and Mapping Agency until 2003. NGA headquarters known as NGA Campus East, is located at Fort Belvoir North Area in Virginia; the agency operates major facilities in the St. Louis, Missouri area, as well as support and liaison offices worldwide; the NGA headquarters, at 2.3 million square feet, is the third-largest government building in the Washington metropolitan area after The Pentagon and the Ronald Reagan Building. In addition to using GEOINT for U. S. military and intelligence efforts, the NGA provides assistance during natural and man-made disasters, security planning for major events such as the Olympic Games. In September 2018, researchers at the National Geospatial-Intelligence Agency released a high resolution terrain map of Antarctica, named the "Reference Elevation Model of Antarctica".
U. S. mapping and charting efforts remained unchanged until World War I, when aerial photography became a major contributor to battlefield intelligence. Using stereo viewers, photo-interpreters reviewed thousands of images. Many of these were of the same target at different angles and times, giving rise to what became modern imagery analysis and mapmaking; the Engineer Reproduction Plant was the Army Corps of Engineers's first attempt to centralize mapping production and distribution. It was located on the grounds of the Army War College in Washington, D. C. Topographic mapping had been a function of individual field engineer units using field surveying techniques or copying existing or captured products. In addition, ERP assumed the "supervision and maintenance" of the War Department Map Collection, effective April 1, 1939. With the advent of the Second World War aviation, field surveys began giving way to photogrammetry, photo interpretation, geodesy. During wartime, it became possible to compile maps with minimal field work.
Out of this emerged AMS, which absorbed the existing ERP in May 1942. It was located at the Dalecarlia Site on MacArthur Blvd. just outside Washington, D. C. in Montgomery County and adjacent to the Dalecarlia Reservoir. AMS was designated as an Engineer field activity, effective July 1, 1942, by General Order 22, OCE, June 19, 1942; the Army Map Service combined many of the Army's remaining geographic intelligence organizations and the Engineer Technical Intelligence Division. AMS was redesignated the U. S. Army Topographic Command on September 1, 1968, continued as an independent organization until 1972, when it was merged into the new Defense Mapping Agency and redesignated as the DMA Topographic Center; the agency's credit union, Constellation Federal Credit Union, was chartered during the Army Map Service era, in 1944. It has continued to serve all successive legacy their families. After the war, as airplane capacity and range improved, the need for charts grew; the Army Air Corps established its map unit, renamed ACP in 1943 and was located in St. Louis, Missouri.
ACP was known as the U. S. Air Force Aeronautical Chart and Information Center from 1952 to 1972. A credit union was chartered for the ACP in 1948, called Aero Chart Credit Union, it was renamed Arsenal Credit Union in 1952, a nod to the St. Louis site's Civil War-era use as an arsenal. Shortly before leaving office in January 1961, President Dwight D. Eisenhower authorized the creation of the National Photographic Interpretation Center, a joint project of the CIA and US DoD. NPIC was a component of the CIA's Directorate of Science and Technology and its primary function was imagery analysis. NPIC became part of the National Imagery and Mapping Agency in 1996. NPIC first identified the Soviet Union's basing of missiles in Cuba in 1962. By exploiting images from U-2 overflights and film from canisters ejected by orbiting Corona s, NPIC analysts developed the information necessary to inform U. S. influence operations during the Cuban Missile Crisis. Their analysis garnered worldwide attention when the Kennedy Administration declassified and made public a portion of the images depicting the Soviet missiles on Cuban soil.
The Defense Mapping Agency was created on January 1, 1972, to consolidate all U. S. military mapping activities. DMA's "birth certificate", DoD Directive 5105.40, resulted from a classified Presidential directive, "Organization and Management of the U. S. Foreign Intelligence Community", which directed the consolidation of mapping functions dispersed among the military services. DMA became operational on July 1, 1972, pursuant to General Order 3, DMA. On Oct. 1, 1996, DMA was folded into the National Imagery and Mapping Agency – which became NGA. DMA was first headquartered at the United States Naval Observatory in Washington, D. C at Falls Church, Virginia, its civilian workforce was concentrated at production sites in Bethesda, Northern Virginia, St. Louis, Missouri. DMA was formed from the Mapping and Geodesy Division, Defense Intelligence Agency, from various mapping-related organizations of the military services. DMA Hydrographic Center DMAHC was formed in
Badakhshan Province is one of the 34 provinces of Afghanistan, located in the farthest northeastern part of the country between Tajikistan and northern Pakistan. It shares a 56.5-mile border with China. It is part of a broader historical Badakhshan region; the province contains 22 to 28 districts, over 1,200 villages, 904,700 people. Feyzabad serves as the provincial capital. Badakhshan is bordered by Gorno-Badakhshan Autonomous Province and Khatlon Province in Tajikistan to the north and east. In the east of the province a long spur called the Wakhan Corridor extends above northern Pakistan's Chitral and Northern Areas to a border with China; the province has a total area of 44,059 square kilometres, most of, occupied by the Hindu Kush and Pamir mountain ranges. Badakhshan was a stopover on the ancient Silk Road trading path, China has shown great interest in the province after the fall of the Taliban, helping to reconstruct roads and infrastructure. According to the World Wildlife Fund, Badakhshan contains temperate grasslands and shrublands, as well as Gissaro-Alai open woodlands along the Pamir River.
Common plants found in these areas include pistachio, walnut, apple and sagebrush. Montane grasslands and shrublands are existent in the province, with the Hindu Kush alpine meadow in the high mountains in the northern and southwestern regions; the Wakhan corridor contains two montane grassland and shrubland regions: the Karakoram-West Tibetan Plateau alpine steppe and in the Pamir Mountains and Kuh-e Safed Khers in Darwaz region. South of Fayzabad the terrain becomes dominated by xeric shrublands. Common vegetation includes thorny bushes, zizyphus and Amygdatus. Paropamisus xeric woodlands can be found in central areas. Common vegetation includes almond, pistachio and sea-buckthorn; the area has a long history like the rest of Afghanistan, dating to its conquering by the Achaemenid Empire and beyond. Badakhshan etymologically derives from an official title; the suffix of the name, -ān, means the region belonged to someone with the title badaxš. The territory was ruled by the Uzbek Khanate of Bukhara between the early 16th century and the mid-18th century.
It was given to Ahmad Shah Durrani by Murad Beg of Bukhara after a treaty of friendship was reached in or about 1750 and became part of the Durrani Empire. It was ruled by the Durranis followed by the Barakzai dynasty, was untouched by the British during the three Anglo-Afghan wars that were fought in the 19th and 20th centuries, it remained peaceful for about 100 years until the 1980s Soviet–Afghan War at which point the Mujahideen began a rebellion against the central Afghan government. During the 1990s, much of the area was controlled by forces loyal to Burhanuddin Rabbani and Ahmad Shah Massoud, who were de facto the national government until 1996. Badakhshan was the only province that the Taliban did not conquer during their rule from 1996 to 2001. However, during the course of the wars a non-Taliban Islamic emirate was established in Badakhshan by Mawlawi Shariqi, paralleling the Islamic Revolutionary State of Afghanistan in neighboring Nuristan. Rabbani, a Badakhshan native, Massoud, were the last remnants of the anti-Taliban Northern Alliance during the peak of Taliban control in 2001.
Badakhshan was thus one of the few provinces of the country that witnessed little insurgency in the Afghan wars - however during the 2010s Taliban insurgents managed to attack and take control of several districts in the province. On 26 October 2015, the 7.5 Mw Hindu Kush earthquake shook northern Afghanistan with a maximum Mercalli intensity of VIII. This earthquake destroyed 30,000 homes, left several hundred dead, more than 1,700 injured; the current Governor of the province is Shah Waliullah Adeeb. His predecessors were Baz Mohammad Ahmadi; the borders with neighboring Tajikistan and Pakistan are monitored by the Afghan Border Police. All law enforcement activities throughout the province are handled by the Afghan National Police. A provincial Police Chief is assigned to lead both the ANP and the ABP; the Police Chief represents the Ministry of the Interior in Kabul. The ANP is backed by the military, including the NATO-led forces. Fayzabad, the capital of Badakhshan province, sits on the Kokcha River and has an approximate population of 50,000.
The chief commercial and administrative center of northeast Afghanistan and the Pamir region, Fayzabad has rice and flour mills. Fayzabad Airport serves the province with regular direct flights to Kabul; the percentage of households with clean drinking water increased from 13% in 2005 to 21% in 2011. The percentage of births attended to by a skilled birth attendant increased from 1.5% in 2003 to 2% in 2011. The overall literacy rate fell from 31% in 2005 to 26% in 2011; the overall net enrolment rate increased from 46% in 2005 to 68% in 2011. Despite massive mineral reserves, Badakhshan is one of the most destitute areas in the world. Opium poppy growing is the only real source of income in the province and Badakhshan has one of the highest rates of maternal mortality in the world, due to the complete lack of health infrastructure, inaccessible locations, bitter winters of the province. BORNA Institute of Higher Education being the first private university located on the bank of Kokcha river. Lapis lazuli has been mined in the Sar-e-Sang mines, located in the Kuran wa Munjan District of Badakhshan, for over 6,000 years.
The mines were the largest and most well-known source in ancient times. Most recent
Ur was an important Sumerian city-state in ancient Mesopotamia, located at the site of modern Tell el-Muqayyar in south Iraq's Dhi Qar Governorate. Although Ur was once a coastal city near the mouth of the Euphrates on the Persian Gulf, the coastline has shifted and the city is now well inland, on the south bank of the Euphrates, 16 kilometres from Nasiriyah in modern-day Iraq; the city dates from the Ubaid period circa 3800 BC, is recorded in written history as a city-state from the 26th century BC, its first recorded king being Mesannepada. The city's patron deity was Nanna, the Sumerian and Akkadian moon god, the name of the city is in origin derived from the god's name, URIM2KI being the classical Sumerian spelling of LAK-32. UNUGKI "the abode of Nanna"; the site is marked by the restored ruins of the Ziggurat of Ur, which contained the shrine of Nanna, excavated in the 1930s. The temple was built in the 21st century BC, during the reign of Ur-Nammu and was reconstructed in the 6th century BC by Nabonidus, the last king of Babylon.
The ruins cover an area of 1,200 metres northwest to southeast by 800 metres northeast to southwest and rise up to about 20 metres above the present plain level. The city, said to have been planned by Ur-Nammu, was divided into neighborhoods, with merchants living in one quarter, artisans in another. There were streets both wide and narrow, open spaces for gatherings. Many structures for water resource management and flood control are in evidence. Houses were constructed from mudbricks and mud plaster. In major buildings, the masonry was strengthened with bitumen and reeds. For the most part, foundations are all. People were buried in chambers or shafts beneath the house floors. Ur was surrounded by sloping ramparts 8 metres high and about 25 metres wide, bordered in some places by a brick wall. Elsewhere, buildings were integrated into the ramparts; the Euphrates river complemented these fortifications on the city's western side. Archaeological discoveries have shown unequivocally that Ur was a major Sumero-Akkadian urban center on the Mesopotamian plain.
The discovery of the Royal Tombs have confirmed its splendour. These tombs, which date to the Early Dynastic IIIa period, contained immense amounts of luxury items made out of precious metals, semi-precious stones, all of which would have required importation from long distances; this wealth, unparalleled up to is a testimony of Ur's economic importance during the Early Bronze Age. Archaeological research of the region has contributed to our understanding of the landscape and long-distance interactions that took place during these ancient times. Ur was a major port on the Persian Gulf, which extended much further inland than it does today, controlled much of the trade into Mesopotamia. Imports to Ur came from many parts of the world; the imported objects include precious metals such as gold and silver, semi-precious stones, namely lapis lazuli and carnelian. It is thought that Ur had a stratified social system including slaves, artisans, doctors and priests. High-ranking priests enjoyed great luxury and lived in mansions.
Tens of thousands of cuneiform texts, including contracts, business records, court documents, record the city's complex economic and legal systems. These texts have been recovered from temples, the palace, individual houses. Excavation in the old city of Ur in 1929 revealed lyres, instruments similar to the modern harp but in the shape of a bull and with eleven strings; when Ur was founded, the Persian Gulf's water level was two-and-a-half metres higher than it is today. Ur is therefore thought to have had marshy surroundings, used canals only for transportation, not for irrigation. Fish, birds and reeds might have supported Ur economically without the need for an agricultural revolution sometimes hypothesized as a prerequisite to urbanization. Archaeologists have discovered the evidence of an early occupation at Ur during the Ubaid period; these early levels were sealed off with a sterile deposit of soil, interpreted by excavators of the 1920s as evidence for the Great Flood of the Book of Genesis and Epic of Gilgamesh.
It is now understood that the South Mesopotamian plain was exposed to regular floods from the Euphrates and the Tigris rivers, with heavy erosion from water and wind, which may have given rise to the Mesopotamian and derivative Biblical Great Flood stories. The further occupation of Ur only becomes clear during its emergence in the third millennium BC; as other Sumerians, the new settlers of Ur were a non-Semitic people who may have come from the east circa 3300 BCE, spoke a language isolate. But during the 3rd millennium BC, a close cultural symbiosis developed between the Sumerians and the East-Semitic Akkadians, which gave rise to widespread bilingualism; the reciprocal influence of the Sumerian language and the Akkadian language is evident in all areas, from lexical borrowing on a massive scale, to syntactic and phonological convergence. This has prompted scholars to refer to Sumerian and Akkadian in the 3rd millennium BC as a Sprachbund; the third millennium BC is described as the Early Bronze Age of Mesopotamia, which ends after the demise of the Third Dynasty of Ur in the 21st century BC.
There are vario