Lehman Caves National Monument
Lehman Caves is actually one cave. It is 402 m ( 1/4 mile) into marble and limestone known as speleothems. The cave is mostly known for its shield formations, described as two curcular heads fastened together. The shields are very similar-looking to many oceanic creatures. Over 300 shields are known to be in the cave. The cave includes: stalactites, stalagmites, helictites, flowstone, popcorn, and other formations.
The cave is located behind an iron door that is protruding from a hillside. If you are wishing to go on a guided tour, the fee is $4 although entry into the park is free. At one point on the tour, all the lights in the cave are turned off so that you may experience total darkness.
This national monument is found in NEVADA