The National Natural Landmarks Program identifies and encourages the conservation of noteworthy sites in the United States natural history. Administered by the National Park Service, the program has designated 599 National Natural Landmarks in the US and American Territories, since it was established on May 18, 1962. These landmarks portray the best illustrations of geological and biological features. The Commonwealth of Kentucky, nicknamed “Bluegrass State”, covers a total area of 40,409 square miles. Kentucky has abundant resources. There are six National Natural Landmarks within Kentucky and one that the state shares with Indiana.
7. Creelsboro Natural Bridge
The privately-owned Creelsboro Natural Bridge, located in Kentucky’s Russell County, was designated in 1987 as a National Natural Landmark. The landmark is a natural bridge made of dolostone and illustrates subterranean stream diversion. Jim Creek occasionally diverts and flows through the tunnel, and the formation process of the bridge continues. A group of hunters discovered the natural bridge in 1770. Creelsboro Natural Bridge is 104 feet long, and the area is a popular camping site.
6. Henderson Sloughs
Henderson Sloughs is a vast wetland in two of Kentucky’s counties, Henderson and Union. In 1974, Henderson Sloughs was designated as a National Natural Landmark covering an area of about 3,949 acres. The site is a significant habitat for waterfowl, with more than 10,000 geese and the same number of ducks every year. The Federal Government, as well as Kentucky’s Department of Fish and Wildlife, own the landmark.
5. Lilley Cornett Woods
Lilly Cornett Woods covers an area of 548 acres and is Kentucky’s only remaining virgin tract of mixed mesophytic forest, located in Letcher County. The National Park Service designated the site as a National Natural Landmark in 1971. The state owns Lilley Cornett Woods through the Eastern Kentucky University. The site has more than 530 flowering plant species. The number of breeding pairs of birds stands at approximately 700. The landmark offers educational programs to about 300 students each year from the Letcher County High School.
4. Red River Gorge
Red River Gorge covers 37,224 acres within the Daniel Boone National Forest in three Kentucky counties: Menifee, Powell, and Wolfe. The canyon system, named Red River Gorge, has an abundance of geological formations, which include over 100 natural arches of sandstone and 41 natural bridges. The site has various ecological zones and diverse flora. Red River Gorge became a National Natural Landmark in 1975. The landmark, owned by the Federal government, is also a National Archaeological site. The Kentuckian, a 1955 film, features the Red River Gorge’s Sky Bridge.
3. Rock Creek Research Natural Area
Located in Kentucky’s Laurel County, Rock Creek Research Natural Area was designated in 1939 as a Research Natural Area and in 1975 as a National Natural Landmark. The area covers 86 acres within the Daniel Boone National Forest and has one of the surviving virgin hemlock-hardwood forests in the state. The Rock Creek Gorge has few access points and lacks trails. The Federal government owns the landmark.
2. Big Bone Lick
Big Bone Lick became a National Natural Landmark in February 2009. The landmark is within Big Bone Lick State Park and covers an area of 510 acres. The park’s addition to the National Register of Historic Places was on June 13, 1972. Located in Boone County, Big Bone Lick has bone beds from the Late Pleistocene, as well as salt springs. The Commonwealth of Kentucky owns the landmark.
1. Ohio Coral Reef
The Ohio Coral Reef is within the Ohio River covering an area of 725 acres in Kentucky’s Jefferson County and Indiana’s Floyd County. The National Park Service designated the Ohio Coral Reef as a National Natural Landmark in 1966. The state-owned landmark is an example of a coral community from the Silurian and Devonian geological periods. The site has many coral species, with specimens indicating close to 900 nominal species.