Prompton State Park is a two thousand-acre public landscape in Wayne County centered on Prompton Lake and notable as an officially undeveloped Pennsylvania state park that is not currently managed by the state conservation department. Its origins lie in the disastrous May 1942 flooding of the Lackawaxen River and Dyberry Creek, which led Congress to fund flood-control dams in 1948; Prompton Dam and reservoir were completed in 1960, and the park opened in 1962. Today it offers lake recreation, fishing, boating, disc golf, and more than twenty-six miles of trails, while local groups help sustain its active public use.