Sylvan Lake, Custer State Park, South Dakota

Sylvan Lake, located within Custer State Park in South Dakota's Black Hills, was formed in 1881 by Theodore Reder's construction of a dam on Sunday Gulch Creek. The lake and its surrounding granite formations are a popular destination for activities such as rock climbing, boating, swimming, and hiking. It also serves as a trailhead for excursions to notable natural landmarks like Black Elk Peak and The Needles.