nuclear fallout shelter. Geology Alabaster Caverns State Park is underlain by Permian age sedimentary rocks (~300 to 250 million years old). The main cavern extends into the formation, is about wide and high. The cavern branches into boulder formations and smaller caves. A small perennial stream now flows through the cavern, fed by various lateral tunnels and seepage from the roof. In the geologic past, the river was once capable of completely filling the cavern, as the cave walls and gypsum formations show evidence of sculpting by rapidly flowing water. The air temperature ranges from 52˚F to 58˚ year round in the cavern. Wildlife The cavern is home to five different species of bat. Some are solitary while others are colonial. The cavern provides roosting sites that serve as daytime shelter and a place for the non-migrating bats to hibernate during the winter months. Mexican free-tailed bats migrate to Alabaster Caverns from Mexico in the spring to bear their young. They then return to Mexico in the fall. The bat species found in the cave are the cave myotis, Western big-eared bat, eastern pipistrelle, Western big brown bat, and the Mexican free-tailed bat. Alabaster Caverns State Park personnel made a count of the bats in the caverns this year and reported over 19,000. In 2016, the count reported about 16,000. Visitor activities Beside guided cave tours, wild caving, camping, hiking trails, and recreational facilities such as horseshoe pits and volleyball courts are available to visitors. Tours are conducted every hour on the hour and last about 45 minutes, and are limited to 40 persons each. The caves are lighted and have plenty of handrails. However, the walking tour is about long and visitors must climb up or down about 330 stair steps. This tour is not recommended for people with mobility or respiratory problems, heart conditions or claustrophobia. Proposed park closure in 2018 In March 2017, the Oklahoma Department of Tourism and Recreation published a list of 16 state parks that may be closed to help offset a reduction in its budget for 2018. Alabaster Canyon State Park is on this list. This list represents approximately one-half of the parks remaining after the department closed seven parks in 2011. Notes References External links Alabaster Caverns State Park Encyclopedia of Oklahoma History and Culture - Alabaster Caverns State Park Caves of Oklahoma State parks of Oklahoma Gypsum caves Show caves in