This weak acid dissolved out cavities in the marble bedrock. Eventually, the water level dropped, leaving air-filled passageways ready for the next stage of cave development. Seeping water continues to enter the cave at a slow rate. Many of the beautiful formations in Lehman Caves are still growing, and are very fragile. Humans take care as they visit the caverns to enjoy, but not disrupt, the formations still changing by the act of water.
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