vania-janet/multiturn-rag-retrieval-data huggingface dataset:
Ghaggar-Hakra River
Paleobotanical information also documents the aridity that developed after the drying up of the river . ( Gadgil and Thapar 1990 and references therein ) . The disappearance of the river may additionally have been caused by earthquakes which may have led to the redirection of its tributaries . It has also been suggested that the loss of rainfall in much of its catchment area as well as deforestation and overgrazing may have also contributed to the drying up of the river . However , a similar phenomenon , caused by climate change , is also seen at about the same period north of the Hindu Kush , in the area of the Bactria - Margiana Archaeological Complex .
Siege
In the European Middle Ages , virtually all large cities had city walls -- Dubrovnik in Dalmatia is a well - preserved example -- and more important cities had citadels , forts , or castles . Great effort was expended to ensure a good water supply inside the city in case of siege . In some cases , long tunnels were constructed to carry water into the city . Complex systems of underground tunnels were used for storage and communications in medieval cities like Tábor in Bohemia , similar to those used much later in Vietnam during the Vietnam War .
Ancient Roman architecture
Concrete quickly supplanted brick as the primary building material , and more daring buildings soon followed , with great pillars supporting broad arches and domes rather than dense lines of columns suspending flat architraves . The freedom of concrete also inspired the colonnade screen , a row of purely decorative columns in front of a load - bearing wall . In smaller - scale architecture , concrete 's strength freed the floor plan from rectangular cells to a more free - flowing environment . Most of these developments are described by Vitruvius , writing in the first century AD in his work De Architectura .
Colosseum
The site chosen was a flat area on the floor of a low valley between the Caelian , Esquiline and Palatine Hills , through which a canalised stream ran . By the 2nd century BC the area was densely inhabited . It was devastated by the Great Fire of Rome in AD 64 , following which Nero seized much of the area to add to his personal domain . He built the grandiose Domus Aurea on the site , in front of which he created an artificial lake surrounded by pavilions , gardens and porticoes . The existing Aqua Claudia aqueduct was extended to supply water to the area and the gigantic bronze Colossus of Nero was set up nearby at the entrance to the Domus Aurea . Cross-section
Ghaggar-Hakra River
Other research using dating of zircon sand grains has shown that subsurface river channels near the Indus Valley Civilisation sites in Cholistan immediately below the dry Ghaggar - Hakra bed show sediment affinity not with the Ghagger - Hakra , but instead with the Beas River in the western sites and the Sutlej and the Yamuna in the eastern ones , further weakening the hypothesis that the Ghaggar - Hakra was once a large river , but suggesting that the Yamuna itself , or a channel of the Yamuna , along with a channel of the Sutlej may have flowed west some time between 47,000 BCE and 10,000 BCE , well before the beginnings of Indus civilization .
Maya civilization
By 6000 BC , the early inhabitants of Mesoamerica were experimenting with the domestication of plants , a process that eventually led to the establishment of sedentary agricultural societies . The diverse climate allowed for wide variation in available crops , but all regions of Mesoamerica cultivated the base crops of maize , beans , and squashes . All Mesoamerican cultures used Stone Age technology ; after c. 1000 AD copper , silver and gold were worked . Mesoamerica lacked draft animals , did not use the wheel , and possessed few domesticated animals ; the principal means of transport was on foot or by canoe . Mesoamericans viewed the world as hostile and governed by unpredictable deities . The ritual Mesoamerican ballgame was widely played . Mesoamerica is linguistically diverse , with most languages falling within a small number of language families -- the major families are Mayan , Mixe -- Zoquean , Otomanguean , and Uto - Aztecan ; there are also a number of smaller families and isolates . The Mesoamerican language area shares a number of important features , including widespread loanwords , and use of a vigesimal number system .
Ancient Roman architecture
Gardens were not reserved for the extremely wealthy . Excavations in Pompeii show that gardens attaching to residences were scaled down to meet the space constraints of the home of the average Roman . Modified versions of Roman garden designs were adopted in Roman settlements in Africa , Gaul , and Britannia . As town houses were replaced by tall insula ( apartment buildings ) , these urban gardens were replaced by window boxes or roof gardens .
Technological and industrial history of the United States
North America has been inhabited continuously since approximately 10,000 BC . The earliest inhabitants were nomadic , big - game hunter - gatherers who crossed the Bering land bridge . These first Native Americans relied upon chipped - stone spearheads , rudimentary harpoons , and boats clad in animal hides for hunting in the Arctic . As they dispersed within the continent , they encountered the varied temperate climates in the Pacific northwest , central plains , Appalachian woodlands , and arid Southwest , where they began to make permanent settlements . The peoples living in the Pacific northwest built wooden houses , used nets and weirs to catch fish , and practiced food preservation to ensure longevity of their food sources , although substantial agriculture was not developed . Peoples living on the plains remained largely nomadic ( some practiced agriculture for parts of the year ) and became adept leather workers as they hunted buffalo while people living in the arid southwest built adobe buildings , fired pottery , domesticated cotton , and wove cloth . Tribes in the eastern woodlands and Mississippian Valley developed extensive trade networks , built pyramid - like mounds , and practiced substantial agriculture while the peoples living in the Appalachian Mountains and coastal Atlantic practiced highly sustainable forest agriculture and were expert woodworkers . However , the populations of these peoples were small and their rate of technological change was very low . Indigenous peoples did not domesticate animals for drafting or husbandry , develop writing systems , or create bronze or iron - based tools like their European / Asian counterparts .
Pre-Columbian era
While many city - states , kingdoms , and empires competed with one another for power and prestige , Mesoamerica can be said to have had five major civilizations : the Olmec , Teotihuacan , the Toltec , the Mexica and the Maya . These civilizations ( with the exception of the politically fragmented Maya ) extended their reach across Mesoamerica -- and beyond -- like no others . They consolidated power and distributed influence in matters of trade , art , politics , technology , and theology . Other regional power players made economic and political alliances with these civilizations over the span of 4,000 years . Many made war with them , but almost all peoples found themselves within one of their spheres of influence .
Ancient Roman architecture
Roman engineering -- Romans are famous for their advanced engineering accomplishments , although some of their own inventions were improvements on older ideas , concepts and inventions . Roman watermill
Ancient Greek architecture
The climate of Greece is maritime , with both the coldness of winter and the heat of summer tempered by sea breezes . This led to a lifestyle where many activities took place outdoors . Hence temples were placed on hilltops , their exteriors designed as a visual focus of gatherings and processions , while theatres were often an enhancement of a naturally occurring sloping site where people could sit , rather than a containing structure . Colonnades encircling buildings , or surrounding courtyards provided shelter from the sun and from sudden winter storms .
Amazon River
Shell mounds were the earliest evidences of habitation ; they represent piles of human refuse and are mainly dated between 7500 and 4000 years BP . They are associated with ceramic age cultures ; no preceramic shell mounds have been documented so far by archaeologists . Artificial earth platforms for entire villages are the second type of mounds . They are best represented by the Marajoara culture . Figurative mounds are the most recent types of occupation .
Siege
Later , the walls of Babylon , reinforced by towers , moats , and ditches , gained a similar reputation . In Anatolia , the Hittites built massive stone walls around their cities atop hillsides , taking advantage of the terrain . In Shang Dynasty China , at the site of Ao , large walls were erected in the 15th century BC that had dimensions of 20 m ( 66 ft ) in width at the base and enclosed an area of some 2,100 yards ( 1,900 m ) squared . The ancient Chinese capital for the State of Zhao , Handan , founded in 386 BC , also had walls that were 20 m ( 66 ft ) wide at the base ; they were 15 m ( 49 ft ) tall , with two separate sides of its rectangular enclosure at a length of 1,530 yd ( 1,400 m ) .
Colosseum
During the early days of the Colosseum , ancient writers recorded that the building was used for naumachiae ( more properly known as navalia proelia ) or simulated sea battles . Accounts of the inaugural games held by Titus in AD 80 describe it being filled with water for a display of specially trained swimming horses and bulls . There is also an account of a re-enactment of a famous sea battle between the Corcyrean ( Corfiot ) Greeks and the Corinthians . This has been the subject of some debate among historians ; although providing the water would not have been a problem , it is unclear how the arena could have been waterproofed , nor would there have been enough space in the arena for the warships to move around . It has been suggested that the reports either have the location wrong , or that the Colosseum originally featured a wide floodable channel down its central axis ( which would later have been replaced by the hypogeum ) .
Dasht-e Kavir
The extreme heat and many storms in Dasht - e Kavir cause extensive erosion , which makes it almost impossible to cultivate the lands . The desert is almost uninhabited and knows little exploitation . Camel and sheep breeding and agriculture are the sources of living to the few people living on its soil . Human settling is restricted to some oases , where wind - blocking housing constructions are raised to deal with the harsh weather conditions . For irrigation , Iranians developed a sophisticated system of water - wells known as qanats . These are still in use , and modern globally used water - revenue systems are based on their techniques .
Olmec
Although the river banks were used to plant crops between flooding periods , the Olmecs probably also practiced swidden ( or slash - and - burn ) agriculture to clear the forests and shrubs , and to provide new fields once the old fields were exhausted . Fields were located outside the village , and were used for maize , beans , squash , manioc , and sweet potato . Based on archaeological studies of two villages in the Tuxtlas Mountains , it is known that maize cultivation became increasingly important to the Olmec over time , although the diet remained fairly diverse .
Colosseum
Two hundred and forty mast corbels were positioned around the top of the attic . They originally supported a retractable awning , known as the velarium , that kept the sun and rain off spectators . This consisted of a canvas - covered , net - like structure made of ropes , with a hole in the center . It covered two - thirds of the arena , and sloped down towards the center to catch the wind and provide a breeze for the audience . Sailors , specially enlisted from the Roman naval headquarters at Misenum and housed in the nearby Castra Misenatium , were used to work the velarium . Entrance
Ancient Roman architecture
Roman arch bridges were usually semicircular , although a few were segmental ( such as Alconétar Bridge ) . A segmental arch is an arch that is less than a semicircle . The advantages of the segmental arch bridge were that it allowed great amounts of flood water to pass under it , which would prevent the bridge from being swept away during floods and the bridge itself could be more lightweight . Generally , Roman bridges featured wedge - shaped primary arch stones ( voussoirs ) of the same in size and shape . The Romans built both single spans and lengthy multiple arch aqueducts , such as the Pont du Gard and Segovia Aqueduct . Their bridges featured from an early time onwards flood openings in the piers , e.g. in the Pons Fabricius in Rome ( 62 BC ) , one of the world 's oldest major bridges still standing . Roman engineers were the first and until the industrial revolution the only ones to construct bridges with concrete , which they called Opus caementicium . The outside was usually covered with brick or ashlar , as in the Alcántara bridge .
Euphrates
During the Jemdet Nasr ( 3600 -- 3100 BCE ) and Early Dynastic periods ( 3100 -- 2350 BCE ) , southern Mesopotamia experienced a growth in the number and size of settlements , suggesting strong population growth . These settlements , including Sumero - Akkadian sites like Sippar , Uruk , Adab and Kish , were organized in competing city - states . Many of these cities were located along canals of the Euphrates and the Tigris that have since dried up , but that can still be identified from remote sensing imagery . A similar development took place in Upper Mesopotamia , Subartu and Assyria , although only from the mid 3rd millennium and on a smaller scale than in Lower Mesopotamia . Sites like Ebla , Mari and Tell Leilan grew to prominence for the first time during this period .
Ghaggar-Hakra River
Along the course of the Ghaggar - Hakra river , there are many early archaeological sites belonging to the Indus Valley Civilization ; but not further south than the middle of Bahawalpur district . It has been assumed that the Sarasvati ended there in a series of terminal lakes , and some think that its water only reached the Indus or the sea in very wet rainy seasons . However , satellite images seem to contradict this : they do not show subterranean water in reservoirs in the dunes between the Indus and the end of the Hakra west of Fort Derawar / Marot .
Ancient Egypt
In Predynastic and Early Dynastic times , the Egyptian climate was much less arid than it is today . Large regions of Egypt were covered in treed savanna and traversed by herds of grazing ungulates . Foliage and fauna were far more prolific in all environs and the Nile region supported large populations of waterfowl . Hunting would have been common for Egyptians , and this is also the period when many animals were first domesticated .
Black Hills
Although written history of the region begins with the Sioux domination of the land over the native Arikara tribes , researchers have carbon - dating and stratigraphic records to analyze the early history of the area . Scientists have been able to utilize carbon - dating to evaluate the age of tools found in the area , which indicate a human presence that dates as far back as 11,500 BC with the Clovis culture . Stratigraphic records indicate environmental changes in the land , such as flood and drought patterns . For example , large - scale flooding of the Black Hill basins occurs at a probability rate of 0.01 , making such floods occur once in every 100 years . However , during The Medieval Climate Anomaly , or the Medieval Warm Period , flooding increased in the basins . A stratigraphic record of the area shows that during this 400 - year period , thirteen 100 - year floods occurred in four of the region 's basins , while the same four basins from the previous 800 years only experienced nine floods .
Siege
The philosophically pacifist Mohists ( followers of the philosopher Mozi ) of the 5th century BC believed in aiding the defensive warfare of smaller Chinese states against the hostile offensive warfare of larger domineering states . The Mohists were renowned in the smaller states ( and the enemies of the larger states ) for the inventions of siege machinery to scale or destroy walls . These included traction trebuchet catapults , eight - foot - high ballistas , a wheeled siege ramp with grappling hooks known as the Cloud Bridge ( the protractable , folded ramp slinging forward by means of a counterweight with rope and pulley ) , and wheeled ' hook - carts ' used to latch large iron hooks onto the tops of walls to pull them down . Cahir
Maya civilization
Trade was a key component of Maya society , and in the development of the Maya civilization . The cities that grew to become the most important usually controlled access to vital trade goods , or portage routes . Cities such as Kaminaljuyu and Q'umarkaj in the Guatemalan Highlands , and Chalchuapa in El Salvador , variously controlled access to the sources of obsidian at different points in Maya history . The most important cities in the northern Yucatán Peninsula controlled access to the sources of salt . In the Postclassic , the Maya engaged in a flourishing slave trade with wider Mesoamerica .
Indus River
The major cities of the Indus Valley Civilisation , such as Harappa and Mohenjo - daro , date back to around 3300 BC , and represent some of the largest human habitations of the ancient world . The Indus Valley Civilisation extended from across northeast Afghanistan to Pakistan and northwest India , with an upward reach from east of Jhelum River to Ropar on the upper Sutlej . The coastal settlements extended from Sutkagan Dor at the Pakistan , Iran border to Kutch in modern Gujarat , India . There is an Indus site on the Amu Darya at Shortughai in northern Afghanistan , and the Indus site Alamgirpur at the Hindon River is located only 28 km ( 17 mi ) from Delhi . To date , over 1,052 cities and settlements have been found , mainly in the general region of the Ghaggar - Hakra River and its tributaries . Among the settlements were the major urban centres of Harappa and Mohenjo - daro , as well as Lothal , Dholavira , Ganeriwala , and Rakhigarhi . Only 90 -- 96 of more than 800 known Indus Valley sites have been discovered on the Indus and its tributaries . The Sutlej , now a tributary of the Indus , in Harappan times flowed into the Ghaggar - Hakra River , in the watershed of which were more Harappan sites than along the Indus .
Pantheon, Rome
Mark Wilson Jones has attempted to explain the design adjustments carried out in relating the porch to the dome , arguing that the Pantheon 's porch was originally designed for monolithic granite columns with shafts 50 Roman feet tall ( weighing about 100 tons ) and capitals 10 Roman feet tall in the Corinthian style . The taller porch would have hidden the second pediment visible on the intermediate block . Instead , after the intended columns failed to arrive , the builders made many awkward adjustments in order to use shafts 40 Roman feet tall and capitals eight Roman feet tall . This substitution was probably a result of logistical difficulties at some stage in the construction . Alternatively , it has also been argued that the scale of the portico related to the urban design of the space in front of the temple . The grey granite columns that were actually used in the Pantheon 's pronaos were quarried in Egypt at Mons Claudianus in the eastern mountains . Each was 39 feet ( 11.9 m ) tall , 5 feet ( 1.5 m ) in diameter , and 60 tons in weight . These were dragged more than 100 km ( 62 miles ) from the quarry to the river on wooden sledges . They were floated by barge down the Nile River when the water level was high during the spring floods , and then transferred to vessels to cross the Mediterranean Sea to the Roman port of Ostia . There , they were transferred back onto barges and pulled up the Tiber River to Rome . After being unloaded near the Mausoleum of Augustus , the site of the Pantheon was still about 700 metres away . Thus , it was necessary to either drag them or to move them on rollers to the construction site .
Ancient Egypt
The ancient Egyptians placed a great value on hygiene and appearance . Most bathed in the Nile and used a pasty soap made from animal fat and chalk . Men shaved their entire bodies for cleanliness ; perfumes and aromatic ointments covered bad odors and soothed skin . Clothing was made from simple linen sheets that were bleached white , and both men and women of the upper classes wore wigs , jewelry , and cosmetics . Children went without clothing until maturity , at about age 12 , and at this age males were circumcised and had their heads shaved . Mothers were responsible for taking care of the children , while the father provided the family 's income . The
Drinking water supply and sanitation in the United States
In the 19th century numerous American cities were afflicted with major outbreaks of disease , including cholera in 1832 , 1849 and 1866 and typhoid in 1848 . The fast - growing cities did not have sewers and relied on contaminated wells within the city confines for drinking water supply . In the mid-19th century many cities built centralized water supply systems . However , initially these systems provided raw river water without any treatment . Only after John Snow established the link between contaminated water and disease in 1854 and after authorities became gradually convinced of that link , water treatment plants were added and public health improved . Sewers were built since the 1850s , initially based on the erroneous belief that bad air ( miasma theory ) caused cholera and typhoid . It took until the 1890s for the now universally accepted germ theory of disease to prevail .
Pre-Columbian era
On the north - central coast of present - day Peru , Norte Chico or Caral ( as known in Peru ) was a civilization that emerged around 3000 BCE ( contemporary with urbanism 's rise in Mesopotamia . ) It is considered one of the six cradles of civilization in the world . It had a cluster of large - scale urban settlements of which the Sacred City of Caral , in the Supe valley , is one of the largest and best studied sites . Norte Chico or Caral is the oldest known civilization in the Americas and persisted until around 1800 BCE . Valdivia
Ancient Egypt
The culture and monuments of ancient Egypt have left a lasting legacy on the world . The cult of the goddess Isis , for example , became popular in the Roman Empire , as obelisks and other relics were transported back to Rome . The Romans also imported building materials from Egypt to erect Egyptian - style structures . Early historians such as Herodotus , Strabo , and Diodorus Siculus studied and wrote about the land , which Romans came to view as a place of mystery .
Maya civilization
During the 9th century AD , the central Maya region suffered major political collapse , marked by the abandonment of cities , the ending of dynasties , and a northward shift in activity . No universally accepted theory explains this collapse , but it likely had a combination of causes , including endemic internecine warfare , overpopulation resulting in severe environmental degradation , and drought . During this period , known as the Terminal Classic , the northern cities of Chichen Itza and Uxmal showed increased activity . Major cities in the northern Yucatán Peninsula continued to be inhabited long after the cities of the southern lowlands ceased to raise monuments .
Siege
As a siege progressed , the surrounding army would build earthworks ( a line of circumvallation ) to completely encircle their target , preventing food , water , and other supplies from reaching the besieged city . If sufficiently desperate as the siege progressed , defenders and civilians might have been reduced to eating anything vaguely edible -- horses , family pets , the leather from shoes , and even each other .