Due to COVID-19, Hidden River Cave is
closed to the public until further notice.
Hidden River Cave, City of Horse Cave, Hart County, 10 acres in three tracts.
This cave is part of a large karst system that drains 100 square miles in West-Central Kentucky and is connected to Mammoth Cave, the largest cave system in the world with over 350 miles of underground passages. The entrance, located in downtown Horse Cave, is a large sinkhole and the water in the cave flows under the city of Horse Cave and re-emerges along the Green River as springs of which five of the largest springs in Kentucky are associated with this karst system in Hart County. It originally opened as Horse Cave around the turn of the century. Tours were routinely given from 1927 until 1943. This cave was once known as the most polluted cave in North America due to industrial and domestic waste issues and it was closed from 1943 until 1993 when a new waste treatment facility began treating those problems. This is significant because the water from the cave system enters the Green River which is one of the most important freshwater streams left in North America and supports more than 70 mussel species of which 17 are rare and one is the only Kentucky endemic, 150 species of fish of which 13 are rare including 7 endemics, the federally endangered KY cave shrimp, the endemic bottlebrush crayfish, and numerous other rare organisms. The cave itself has no spectacular formations but does provide habitat for unique cave critters including the state special concern southern cavefish and eyeless crayfish, two trogolbitic invertebrates including an isopod and amphipod, and a copepod which is only known from one other location. The purpose of protecting this land was to protect and manage Hidden River Cave and to work with the American Cave Conservation Association to provide an example of how to protect an underground cave and watershed from the threats of inadequate sewage treatment, contaminants from traffic and businesses, spills from trains intrusions of oil and gas drilling and pollution from agricultural runoff. The ultimate goal is to develop an education program in coordination with the American Cave Conservation Association.