Lake Oahe

Lake Oahe () is a large reservoir behind the Oahe Dam on the Missouri River; it begins in central South Dakota and continues north into North Dakota in the United States. The lake has an area of 370,000 acres (1,500 km2) and a maximum depth of 205 ft (62 m). By volume, it is the fourth-largest reservoir in the US. Lake Oahe has a length of approximately 231 mi (372 km) and has a shoreline of 2,250 mi (3,620 km). 51 recreation areas are located along Lake Oahe, and 1.5 million people visit the reservoir every year. The lake is named for the 1874 Oahe Indian Mission. Lake Oahe begins just north of Pierre, South Dakota and extends nearly as far north as Bismarck, North Dakota. Mobridge, South Dakota is located on the eastern shore of the central portion of the lake. Bridges over Lake Oahe include US Route 212 west of Gettysburg, South Dakota and US Route 12 at Mobridge. The former town of Forest City has been flooded beneath Lake Oahe, about 9 miles west of Gettysburg. Prehistoric archaeological sites have been explored in the area, including Molstad Village near Mobridge. It dates to before the emergence of the Arikara, Hidatsa, and Mandan as separate peoples, and has been designated as a National Historic Landmark.