Longhorn Cavern State Park in Burnet County centers on a limestone cave formed by an underground river long ago and later used by Native Americans and Confederate soldiers; stories linking it to Sam Bass remain unverified. In the late 1920s and early 1930s, the cave, then called Sherrard's Cave, became a nightclub with live music and radio broadcasts. Texas acquired the land between 1932 and 1937, and the park opened to the public in 1938. Civilian Conservation Corps Company 854 built roads and rustic park structures and made the cavern accessible. Later recognized as a National Natural Landmark, the site continues to host music, performances, trails, wildlife, and filming.