Lake Mineral Wells State Park& Trailway is a state park located in Mineral Wells, Parker County, Texas. It includes Lake Mineral Wells, and is the only state park in Texas which protects part of the Western Cross Timbers and Mineral Wells Trailway. Also within the park is Penitentiary Hollow, a somewhat unusual geological feature which resembles a small canyon. It is a popular site for rock climbing, though the only type of climbing allowed is top-rope.