Training Dike Recreation Area is a U.S. Army Corps of Engineers site just downstream from Gavins Point Dam and Lewis and Clark Lake near Yankton, occupying the narrow Training Dike between the Missouri River and Lake Yankton. Built after the dam’s completion, the dike was intended to channel the river as it left the dam and power plant into its present course. Though often assumed to be in South Dakota because it lies on the river’s north bank, most of the area is actually in Nebraska, since the state line follows the river’s original main channel. Today it is a popular day-use destination for fishing, boating, trails, swimming, picnicking, and prairie restoration.