Carlsbad Caverns National Park is located in the Guadalupe Mountains of southeastern New Mexico. Carlsbad Cavern is one of over 300 limestone caves in a fossil reef laid down by an inland sea 250 to 280 million years ago. Marine fossils have been found in the rock.The caverns were forged by sulfuric acid – not water erosion, as is the case with most limestone caves and there are no flowing rivers or streams inside the caves.
The park is home to a large number of Mexican Free-tail bats. It was these bats’ guano that was deposited on the floor of the cave and sparked the guano mining industry. It is estimated that the population once ranged in the millions.
Carlsbad Caverns National Park was first designated a National Monument in 1923. It became a National Park in 1930. Carlsbad Caverns was also designated a UNESCO World Heritage Site in 1995.
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