The cave system contains a large underground creek that courses around much of the cave's nearly 16 miles (26 km) of passages. The cave system has some unusual features such as its rate of expansion, which is higher than that of most caves. It also has relatively low amounts of oxygen and high amounts of carbon dioxide. The cave is a National Natural Landmark, designated in 1987.

• http://en.wikipedia.org/wiki/Cold Water Spring State Preserve