Longhorn Cavern State Park, south of Burnet in Burnet County, is 645.62 acres classified as a scenic park in the rugged Hill Country. Longhorn Cavern was acquired in 1932 - 1937 from private owners. It was dedicated as a state park in 1932, was opened in 1938, and was dedicated as a natural landmark in 1971.
During the last million years, the water deposited a thick layer of mud and debris in the cave. Early visitors were restricted to a small area due to this debris. Some of the earliest visitors were the area’s prehistoric peoples, who used the large room next to the main entrance for shelter. Anglo settlers discovered the cavern in the mid-1800s and began mining bat guano, which was used in manufacturing gun powder during the Civil War.
The cave has been used as a shelter since prehistoric times. Among legends about the cave is one that the outlaw Sam Bass hid a $2 million cache of stolen money inside. Confederates made gunpowder in the cave during the Civil War. Legend also says Texas Rangers rescued a kidnapped girl from Indians in the cave.
There is no evidence that Sam Bass ever visited the cave, but stories like this one drew tourists as early as the turn of the 20th century. By the 1920s, the main room served as a dance hall and concert venue.
Many of the structures at the park were built by the Civilian Conservation Corps.