Opis
Coordinates: 33°10′53.5″N 44°41′56.9″E / 33.181528°N 44.699139°E
Opis (Akkadian Upî or Upija; Ancient Greek: Ὦπις) was an ancient Babylonian city near the Tigris, not far from modern Baghdad. Akkadian and Greek texts indicate that it was located on the east side of the Tigris, near the Diyala River. While the precise site of the city has been considered uncertain for a long time, recent geographical surveys of ancient Mesopotamia identify Opis with great probability as the mound called Tall al-Mujailāt (or Tulūl al-Mujaili`), 20 miles (32 km) southeast in a straight line from central Baghdad and 47 miles (76 km) northeast in a straight line from ancient Babylon.
Opis is mentioned for the first time at the beginning of second millennium BC. In the 14th century BC, it became the capital of an administrative region in Babylonia.
The Babylonians dug the "royal canal" between the Euphrates and the Tigris, which ended near Opis. The Babylonian king Nebuchadnezzar II (605–562 BC) built a long wall between the two rivers to protect against a potential Median invasion; the fortified line continued eastward beyond the Tigris and ended near Opis.
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