Pyramidal, stepped temple tower characteristic of the major cities of Mesopotamia between 2200 and 500 BC.
It was built with a core of mud brick and an exterior covered with baked brick. It had no internal chambers and was usually square or rectangular. Some 25 ziggurats are known, located in Sumer , Babylonia , and Assyria . The best-preserved ziggurat is at Ur , and the largest is at Elam . The legendary Tower of Marduk in Babylon .