Lake Oahe spans 231 miles from Pierre, the capital of South Dakota, to Bismarck, the capital of North Dakota. Lake Oahe is surrounded by mixed grass prairie with trees growing down to the shore in occasional steep draws. People travel from all over the nation to participate in recreational activities on the 461,000 acres of land and water that comprise the project. Guests are encouraged to have fun and are reminded that care should be taken to preserve the lands and waters for future visitors.