Wind Cave National Park

10 mi. north of Hot Springs is the Wind Cave, part of one of the largest karstic cave systems so far found on earth. It was discovered in 1881 when a hunter noticed a strong current of air emerging from a narrow cleft in the rock. Differing air pressures inside and outside the cave produce air currents that can reach a speed of up to 50 mi. an hour. A local peculiarity is the occurrence of very delicate honeycomb structures of brown calcareous spar known as "boxwork". Part of the cave system can be visited.

On the beautiful park-like "roof" of the cave system, now a National Park, several hundred bison graze.