Osage State Fishing Lake is a state-owned reservoir in northern Osage County, Kansas, built in 1955 and set within 366 acres of mostly tallgrass prairie and wooded parkland. The 140-acre freshwater lake is managed chiefly for outdoor recreation, especially fishing, with excellent channel catfish fishing and good largemouth bass and bluegill fishing, as well as boating, camping, and limited hunting. Fourteen fishing piers, a boat ramp, and gravel roads serve the area, though some low road sections can flood. Beyond recreation, the site preserves visible wagon ruts from the nineteenth-century Santa Fe Trail along the lake’s north edge.