<P> The word dam can be traced back to Middle English, and before that, from Middle Dutch, as seen in the names of many old cities . The first known appearance of dam occurs in 1165 . However, there is one village, Obdam, that is already mentioned in 1120 . The word seems to be related to the Greek word taphos, meaning "grave" or "grave hill". So the word should be understood as "dike from dug out earth". The names of more than 40 places (with minor changes) from the Middle Dutch era (1150--1500 CE) such as Amsterdam (founded as' Amstelredam' in the late 12th century) and Rotterdam, also bear testimony to the use of the word in Middle Dutch at that time . </P> <P> Early dam building took place in Mesopotamia and the Middle East . Dams were used to control the water level, for Mesopotamia's weather affected the Tigris and Euphrates rivers . </P> <P> The earliest known dam is the Jawa Dam in Jordan, 100 kilometres (62 mi) northeast of the capital Amman . This gravity dam featured an originally 9 - metre - high (30 ft) and 1 m - wide (3.3 ft) stone wall, supported by a 50 m - wide (160 ft) earth rampart . The structure is dated to 3000 BC . </P> <P> The Ancient Egyptian Sadd - el - Kafara Dam at Wadi Al - Garawi, located about 25 km (16 mi) south of Cairo, was 102 m (335 ft) long at its base and 87 m (285 ft) wide . The structure was built around 2800 or 2600 BC as a diversion dam for flood control, but was destroyed by heavy rain during construction or shortly afterwards . During the Twelfth Dynasty in the 19th century BC, the Pharaohs Senosert III, Amenemhat III and Amenmehat IV dug a canal 16 km (9.9 mi) long linking the Fayum Depression to the Nile in Middle Egypt . Two dams called Ha - Uar running east - west were built to retain water during the annual flood and then release it to surrounding lands . The lake called "Mer - wer" or Lake Moeris covered 1,700 km (660 sq mi) and is known today as Berkat Qaroun . </P>

Who built the first dam in the world
find me the text answering this question