Rostock is the largest city in the German state of Mecklenburg-Western Pomerania, situated in the Mecklenburgian part of the region near the border with Pomerania. It lies on the estuary of the River Warnow as it flows into the Bay of Mecklenburg of the Baltic Sea. The city stretches approximately 16 kilometers along the river, with its center located further upstream in the southern part of the urban area.