Inks Lake State Park

Devil's Waterhole — a small arm of Inks Lake almost entirely enclosed by bare rock — is the reason people keep coming back. The park sits in Burnet County on the Colorado River, covers 1,201 acres, and has been open since 1950. The underlying rock is ancient gneiss, dated at 1,232 million years old and named for the park itself. Because the lake level stays nearly constant year-round, the water is reliably there when you show up.