A 980-acre expansion of Mammoth Cave National Park is in the works.

U.S. Sen. Mitch McConnell and Rep. Brett Guthrie on Tuesday unveiled legislation that would allow the park? to acquire “critical habitat” within the Green River watershed from The Nature Conservancy.

“The property includes numerous cave passages, including Coach Cave and James Cave that have prehistoric and historic artifacts that the National Park System can conserve and manage,” said a news release from McConnell’s office.

The two Republican lawmakers from Kentucky introduced the Mammoth Cave National Park Boundary Adjustment Act in their respective chambers. They said the expansion would protect wildlife, preserve cultural heritage and bring more tourism into Guthrie’s Second Congressional District.

Site of the world’s longest known cave system, the 52,000 acre park is a UNESCO World Heritage Site and International Biosphere Reserve.

The news release said the southern boundary expansion includes the coordinates 135/177, 967 in Edmonson and Barren counties.

Guthrie said, “As the world’s longest known cave system full of biodiversity and history, Mammoth Cave National Park is not only a treasure to the Commonwealth of Kentucky, but also a treasure to the entire world. After discussions with Mammoth Cave National Park leadership and the local community, I introduced a bill to allow the park to acquire specific land to put cultural heritage artifacts and habitats under the care and expertise of the Mammoth Cave National Park Service. I’m proud to partner with Leader McConnell on this effort to expand Mammoth Cave National Park for National Park Service employees and volunteers to conserve and people to enjoy for generations to come.”

Said McConnell, the Senate’s Republican leader: “Kentucky is lucky to be home to an abundance of natural treasures, among them, Mammoth Cave National Park. This extensive cave network has been inspiring Kentuckians and drawing visitors from all corners of the globe for generations. Beyond its role in driving tourism to our Commonwealth, the park also plays a crucial role in the region’s economic growth, supporting good jobs for the people of Kentucky,” said McConnell. “I’m proud to partner with Congressman Guthrie on this important initiative once again which will expand the critical habitats that the National Park Service protects and preserves in the park.”