The Choptank River is a major tributary of the Chesapeake Bay and the largest river on the Delmarva Peninsula. Running for 71 miles (114 km), it rises in Kent County, Delaware, runs through Caroline County, Maryland, and forms much of the border between Talbot County, Maryland, on the north, and Caroline County and Dorchester County on the east and south. It is located north of the Nanticoke River, and its mouth is located south of Eastern Bay. Cambridge, the county seat of Dorchester County, and Denton, the county seat of Caroline County, are located on its south shore.