In a karst landscape, mildly acidic groundwater moves through soluble bedrock, dissolving the limestone and dolomite into a subterranean maze of caves and fissures. Much of the Missouri Ozarks is karst, earning its nickname as the Cave State.
The first stop on a tour of the park led by Webb, the naturalist, was a natural bridge, where the trail led under a massive arch in the woods. He explained that the formation was caused by the collapse of a cave roof.
“Basically, that’s a sinkhole here and that’s a portion of the cave that did not collapse,” he said.