Cascade Caverns

The karst limestone beneath the Texas Hill Country hides more than most people bother to look for. Cascade Caverns, outside Boerne, has been running commercial tours since 1932 — long enough to have closed during World War II for gas rationing, been looted during that closure, and reopened anyway. The cave holds mastodon remains, saber-toothed cat bones, and a rare endemic salamander found nowhere else but one neighboring cavern. The waterfall that gave it its name dried up in a 1950s drought; the one running today is artificial, installed to replace it without the flooding risk.