Leaks in the Roof (Stop 6)

Cave formations inside Lehman Caves

NPS

Around 150 feet right below your feet lies Lehman Cave, an amazing and intricate structure that began its existence somewhere between two and ten million years ago and is still growing to this day. Many of the cracks in the limestone on this hillside are miniscule passages into the cave below. As rain falls and seeps into the ground , it picks up a little carbon dioxide from the dead matter in the soil, becoming a weak acidic compound we call carbonic acid. (this same compound can be found in soda you drink!) As this acid makes its way into tiny cracks and crevices in the rock, it dissolves a bit as it goes, picking up some of the native calcite.

Once it reaches the cave, however, the carbon dioxide gets released into the air, just like opening a soda can, and the water can no longer hold onto that mineral it has gathered. The calcite then gets deposited wherever the water seeps out. The resulting diverse speleothems, or cave formations, create an underground world like something from fantasy.