An unnamed arch in Calaveras County, California
Photo by Jay Wilbur
Example CavernNABSQNO 10S-721358-4214870. This unnamed cavern was cut through limestone by Coyote Creek a few miles south of Vallecito, California. The upstream entrance is pictured. In the very near geologic future, this cavern will likely experience roof collapse, turning it into a series of young waterfall natural bridges.
Other Cavern examples: