Tigris–Euphrates river system through the central plain and combine at Al-Qurnah to form the Shatt al-Arab and discharge into the Persian Gulf. The region has historical importance as part of the Fertile Crescent region, in which civilization is believed to have first emerged. The ecoregion is characterized by two large rivers, the Tigris and Euphrates. The rivers have several small tributaries which feed into the system from shallow freshwater lakes, swamps, and marshes, all surrounded by desert. The hydrology of these vast marshes is extremely important to the ecology of the entire upper Persian Gulf. Historically, the area is known as Mesopotamia. As
Euphrates Tunnel Euphrates Tunnel The Euphrates Tunnel was allegedly a tunnel which was built under the Euphrates river to connect the two halves of the city of Babylon, in the old Mesopotamia. Archaeologists believe it was built between 2180 and 2160 BCE. No other sub-aqueous pedestrian tunnel was attempted until Marc Brunel built the Thames Tunnel beginning in 1824 CE. Construction allegedly began with a temporary dam across the Euphrates river, and proceeded using a "cut and cover" technique. The tunnel allegedly spanned 12 feet high and 15 feet wide, it is presumed that it was used by pedestrians and horse driven