Keystone State Park is a seven hundred fourteen-acre Oklahoma state park on Keystone Lake near Sand Springs and Mannford, accessible from State Highway 151. Centered on the lake, it is used chiefly for outdoor recreation and short cabin stays, with fishing, swimming, boating, and water skiing as its main activities. In 2020, Oklahoma added a vehicle entrance fee at the park as part of a broader effort to address deferred maintenance and support park improvements. The fee program included exemptions for some residents and veterans, along with options for multi-day and annual passes.