The most important city of southern Mesopotamia during the early Old Babylonian period, one of the city-states of Sumer. It was located on the Euphrates River between Ur and Babylon, southeast of Uruk, southern Iraq. Archaeological remains are found in a group of tells, though most of its history has been recovered from documents from other sites. It emerged as a city-state during the Early Dynastic period, and its period of greatness was in the early 2nd millennium BC, when it contested the supremacy of Mesopotamia with Isin, Assur, and Eshnunna. The first great ruler was Naplanum (reigned c 2025-2005 BC), who was succeeded by 13 kings. Its greatest ruler, Rim Sin, destroyed Isin c 1794 BC but was himself overthrown by Hammurabi of Babylon c 1763. Remains include a ziggurat, a temple to the sun god, and a palace of Nur-Adad (c 1865-1850 BC), as well as many tombs and other remains of the Neo-Babylonian and Seleucid periods. The documented settlement history of the site spans from the late 3rd millennium (Ur III) to the mid-1st millennium (Neo-Babylonian) BC.