Beginning in the late 1940s, the Missouri River was dammed to create four massive reservoirs - Oahe, Sharpe, Francis Case, and Lewis and Clark. Together these massive bodies of water make up South Dakota's Great Lakes Region, providing over 440 miles of waterway for boating, fishing, sailing, swimming and windsurfing. Here you can follow in the footsteps of Lewis and Clark, experience Native American heritage and kick back on the over 3,000 miles of shoreline.