Discovery in Mammoth Cave

Date: September 9, 1972 • Location: Barren County, United States

In Kentucky's Mammoth Cave National Park, a Cave Research Foundation exploration and mapping team discovers a link between the Mammoth and Flint Ridge cave systems, making it the longest known cave passageway in the world.

Kentucky, officially the Commonwealth of Kentucky, is a landlocked state in the Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the northeast, Virginia to the east, Tennessee to the south, and Missouri to the west. Its northern border is defined by the Ohio River. Its capital is Frankfort and its most populous city is Louisville. As of 2024, the state's population was approximately 4.6 million.