Mammoth Cave
National Park
Park Photo
NPS photo

Above and Below: One Ecosystem Linked by Water

Beneath the sandstone and shale ridges of Mammoth Cave National Park lies the most extensive cave system on Earth. After 4,000 years of intermittent exploration, the full extent of this water-formed labyrinth remains unknown. With over 365 miles of surveyed passageways, Mammoth Cave is over twice as long as any known cave. How long might it be? Geologists think there could be 600 miles of undiscovered passageways.

This vast cave system holds one of the world's most diverse cave ecosystems. About 130 forms of life can be found in Mammoth Cave. Most are quite small. Some use the cave only as a haven, while others are such specialized cave dwellers that they can live nowhere else. All depend on energy from the surface. Life in the cave is not separate from the rest of the park's natural communities. It is an extension of the larger biological whole, whose diversity and abundance are preserved in this place. To tour the cave and not explore the park's surface trails and waterways is to gain but half of the total picture here.

The rugged, forested hill country of Mammoth Cave National Park is sanctuary to an array of wildlife. Deer and wild turkey frequently feed near roadsides, and 80 miles of park hiking trails provide access to the diverse life of the eastern hardwood forest. The Green River further enhances the variety of scenery and habitat. Running 27 miles through the park, the Green River is one of North America's most biologically diverse rivers. This abundance has drawn humans to this region for nearly 10,000 years.

Prehistoric peoples explored 10 or more miles of Mammoth Cave 4,000 years ago. Archeological evidence shows that these early cavers collected crystals and other salts in the cave. Cave exploration ceased 2,000 years ago, not to resume until the cave was rediscovered in 1798.

Mammoth Cave played an important role at the very start of American tourism. As an attraction, the cave predates all national parks. Publicized in the War of 1812. the "mammoth" cave of Kentucky became an attraction by 1816. With the early scenic national parks. Mammoth Cave helped define our national identity in the 1800s, when a young United States sought status among world powers. Despite industrial and military might, we lacked the ancient places and cultural antiquities that Europe offered. Wonders of nature were our great treasures. Big was beautiful: Mammoth Cave, Grand Canyon, and Giant Sequoia. These superlatives still live up to what Ralph Waldo Emerson once called "the brag" about them.

A World Heritage Site and Biosphere Reserve

Mammoth Cave was authorized as a national park in 1926 and fully established in 1941. Only 40 miles of passageway had been mapped then. As surveying techniques improved, great strides were made in describing and understanding the cave system's overwhelming extent. Several park caves were shown to be connected, and we now know the cave system extends well beyond the national park boundary. The park was named a World Heritage Site in 1981 and became the core area of an International Biosphere Reserve in 1990. With its 53,000 surface acres and underlying cave ecosystem, Mammoth Cave National Park is an international treasure.

But national park status and international recognition do not guarantee the continued protection and integrity of the natural systems of Mammoth Cave National Park. The park is not a self-contained system. Research shows that the cave and resident ecosystems belong to regional groundwater basins in the much larger Green River basin. Groundwater originates far beyond the park boundary and the quality can be seriously degraded under high-water conditions. Air quality studies detect ozone at concentrations that can damage vegetation. To preserve these world-class cave, forest, and river ecosystems for future generations, we must work together to protect the region's air and watersheds.

Clean Water Needed ...

Limestone underlies the Mammoth Cave region. As rainwater infiltrates the soil, it picks up small amounts of carbon dioxide gas. Carbon dioxide reacts with the water to form a weak carbonic acid, making the groundwater mildly acidic. Like most major caves, Mammoth Cave was formed by the slow dissolution of limestone by groundwater. Animals living in the cave depend on the quantity and quality of this water.

Eroded limestone landscapes—called karst topography—are typified by the Mammoth Cave area. Sediments of a shallow sea covering this region 350 million years ago formed the limestone as highly soluble layers over a 70-million-year period.

... Caves Still Forming

Over time, as groundwater dissolves the limestone, it forms underground streams. These streams converge, as surface streams do, and create Mammoth Cave's underground rivers. Over Mammoth Cave's geologic history the Green River, the region's master stream, has deeply carved and entrenched itself in its valley. Cave streams responded by creating younger, lower routes and abandoning older and higher channels, creating a network of cave passages. At depths of up to 450 feet below the surface, cave streams are still forming passages today.

As the cave formed, many aquatic species from surface waters slowly adapted to cave habitats. Several evolved as the specialized animals now found in cave streams. These cave biological communities are part of a nutrient-poor ecosystem that needs excellent water quality to survive.

The geological character that creates Mammoth Cave also threatens the cave's ecology today. Rainwater-turned-groundwater flows readily through the cave's aquatic habitats, but so do pollutants like human waste, agricultural runoff, hazardous spills on roadways, and oil and gas drilling wastes. These are easily washed into cave streams.

Because most of the cave's groundwater originates beyond the park, the Biosphere Reserve boundary encompasses Mammoth Cave's entire watershed. Today the park and its neighbors work together through the Biosphere Reserve Program to help better protect the cave while promoting environmentally sustainable agricultural, industrial, and business practices outside the park.

Human Use of the Cave and Its Resources

Over 10,000 years ago Paleo-Indians hunted animals in the Green River valley near Mammoth Cave. From 4,000 to 2,000 years ago, Late Archaic and Early Woodland Indians explored and mined minerals from Mammoth and other caves. Artifacts these earliest explorers left—including cane reed torches they used to light their way into distant parts of the cave—are preserved in drier passageways.

European American settlers came to the Green River valley in the late 1790s. Like native people before them, the newcomers found uses for Mammoth Cave. The cave served as a mine for saltpeter, key to the manufacture of gunpowder. Before the War of 1812 enslaved workers mined large quantities of this mineral.

By war's end Mammoth Cave's notoriety had grown. Around 1816 people started to visit the cave. In 1838 Stephen Bishop and Mat and Nick Bransford, enslaved persons owned and leased by the cave's owners, became renowned guides.

Bishop discovered many miles of cave. He was first to cross the previously impassable Bottomless Pit and the first to see the cave stream's natural residents, called eyeless cavefish. The Bransfords and their descendants were guides at Mammoth Cave for over 100 years.

Stephen Bishop was a self-educated enslaved man who became a legendary cave guide and explorer. He began guiding visitors at age 17 in 1838. He was the first person to explore many miles of the vast cave.

Amateur caver Floyd Collins drew national media attention in 1925, pinned for days by a boulder in Sand Cave. He died before rescuers could free him. The publicity played a role in Mammoth Cave being made a national park in 1926.

Touring the Cave

Plan Ahead Cave tours are offered daily, except December 25. Tour schedules and visitor center hours vary from season to season. Fees are charged. Certain tours may require special clothing or equipment. Contact the park for tour descriptions and schedules, or for information on surface activities and special events.

Mammoth Cave National Park
Mammoth Cave, KY 42259-0007

Getting to the Park From Louisville, KY, take I-65 south to exit 53 at Cave City. From Nashville, TN, take I-65 north to exit 48 at Park City, KY.

Time Zone Mammoth Cave National Park and Nashville, TN, are in the Central Time Zone, one hour behind Louisville (Eastern Time Zone).

Reserve a Tour Before You Visit Cave tours can and do sell out. Summer days, holidays, and all weekends are busy. Make advance reservations so you can enjoy the tour of your choice. Call the park or go to

Traveling With Children If your children are very young, consider taking a shorter orientation tour. Children under 16 must be accompanied by an adult. Some tours have other age restrictions. Strollers and child backpack carriers are prohibited in the cave Some tours have restroom facilities, others do not Ask for details.

Are There Things I Can't Take Into the Cave? All weapons are prohibited (firearms, knives, sharp instruments, pepper spray, mace). Camera tripods and monopods are not permitted, nor is flash photography, though you may photograph without a flash. Flashlights are welcome on all tours except lantern tours but may not be used during tour stops. Respect other people. Don't shine lights in their eyes in the dimly lit cave. Except as medically necessary, bring no food or drink other than water.

Clothing and Footwear Wear sturdy shoes or hiking boots with good soles. Some spelunking tours require treaded boots. No bare feet; sandals are not recommended. A light jacket is recommended; cave temperatures range from freezing to around 60°F. In winter, dress in layers.

Protecting Yourself and the Cave Many cave tours are strenuous and require stooping and walking over uneven trails. You must navigate steps on all tours. Use handrails where available. Walk at a comfortable, steady pace behind the lead guide at all times; the slowest pace is at the front of the tour. You must stay with your tour, children must stay with parents, and everyone must stay on defined tour trails. Smoking is prohibited. Do not write on cave walls or collect cave rocks or objects as souvenirs. To guard against the spread of white-nose syndrome, a fungal disease affecting bats, all cave tour participants must walk on biosecurity mats immediately following the tour.

Accessibility We strive to make our facilities, services and programs accessible to all. For more information, call the park or check the park website.

Exploring Mammoth Cave

Erosional forces that formed the cave system shaped the entire region's landscape. Rivers, bluffs, sinkholes, cave entrances, and ridge tops all provide varied habitats with many distinct plant and animal communities. Relatively small, specialized habitats like wetlands and old-growth forests contribute disproportionately to the park's and Kentucky's biological diversity. Largely wooded, the park features mostly second-growth forest, but small areas of relatively undisturbed old-growth forest—rare in Kentucky—are also found. Beech trees dominate ravine flats, joined by yellow poplar and sugar maple on lower and middle slopes. White and black oaks and three species of hickory define upper slope forests.

Park forests are home to a wide variety of wildlife. Eastern white-tailed deer browse roadsides and flocks of wild turkey are often seen. You may notice squirrels, chipmunks, and raccoons—the park's most often-sighted mammals—as you walk the trails.

As the region's base-level stream, the Green River is central to the formation and health of the Mammoth Cave system. One of North America's most biologically diverse rivers, the Green harbors 82 fish species. Gravel bars of the upper Green are critical habitat for freshwater mussels, one of the nation's most endangered animal groups. Over 50 species are found in the park; seven are listed as endangered. Another four are being considered for listing. The banks of the Green River and its largest park tributary, the Nolin River, abound in wildlife. Deer, wood ducks, turtles, kingfishers, and great blue herons are often seen.

Mammoth Cave National Park has many smaller, more specialized habitats having conditions required for various plant and animal communities. Small ponds and stream banks are wetland refuges for at least one rare sedge, several rushes, bladderwort, arrowroot, and the lance-leaved violet. The sinkholes and cave entrances are moist microclimates for plant species unlike those in drier uplands. Native grassland species, once characterizing much of western and central Kentucky, grow in isolated patches and along park roadsides now. Sandstone gorges in the park's northern part support hemlock, yellow birch, umbrella magnolia, and holly.

Don't think of Mammoth Cave National Park in two parts: the cave system's below-ground world and the above-ground realm of forest and light. These are two parts of a greater whole, unified by forces of nature that continue to form the cave, shape the landscape, and nurture their biological communities.

General Information

park map

topo map
(click for larger maps)

Mammoth Cave is about 85 miles from both Louisville, KY, and Nashville, TN. The park is in the Central Time Zone. Airports and car rentals are in Nashville, Louisville, and Bowling Green.

No park entrance fee is charged, but people six years and older must pay tour fees. Fees are charged for camping. Free park publications list visitor center hours, and ranger-led and evening programs. Find a trail map and information on accessible facilities and activities at the visitor center.

Camping Stay at any of the park's three campgrounds for up to 14 days. Toilets, grills, tables, and water, but no hookups, are provided. Houchin Ferry Campground is first-come, first-served. Reservations are recommended for Mammoth Cave and required for Maple Springs Group campgrounds (for large groups and campers with horses). Visit to make reservations.

Backcountry camping is allowed at 13 designated sites, on riverbanks, and on islands, by permit only. Get a free permit at the visitor center.

Scenic Drives Drive Flint Ridge, Green River Ferry, Ugly Creek, Joppa Ridge, and Houchin Ferry roads in your private vehicle. The latter three roads are not passable by trailers or motor homes. Ask for more information at the visitor center.

Ranger-led Programs Attend an above-ground talk or activity at specified locations in season. At Mammoth Cave amphitheater, rangers give evening programs in season. Non-campers may park nearby.

Junior Ranger Program Children ages five and older may become Junior Rangers by answering questions in the Junior Ranger booklet. Ask for it at the visitor center. Groups are not eligible for this family activity, but may qualify for the park's environmental education program.

Trails Heritage and Sand Cave trails, and Sloans Crossing Pond Walk, are all wheelchair-accessible. The park has 65.8 miles of trails north of Green River, and 18 miles of trails south of the river.

Bicycling South of the Green River, bicycles are permitted on the nine-mile Mammoth Cave Railroad Bike and Hike Trail, the Amphitheater Trail, and on some service roads designated in the park's Backcountry Map & Guide. North of the river, mountain biking is permitted on Big Hollow, Maple Springs, and White Oak trails. Ask for maps and mountain biking information at the visitor center.

Boating and Canoeing Nearly 30 miles of the Green and Nolin rivers offer canoeing and boating, past high bluffs. Commercial outfitters outside the park rent canoes, kayaks, and safety equipment.

Fishing Muskie, bass, crappie, and catfish await anglers in the Green and Nolin rivers. Fishing licenses are not required in the park, but all other Kentucky fishing regulations apply. Ask for regulations at the visitor center.

Horse Use Most trails north of the Green River are open for horseback riding. You must stay on designated trails. Do not hitch horses to trees. Commercial liveries outside the park rent horses, and some may provide organized excursions.

Pets The Lodge at Mammoth Cave has a kennel; fees apply. Only service animals are permitted in the cave. Pets left in parked vehicles may be removed by park staff when temperatures threaten the animals' lives. Pets must be kept on leashes, no more than six feet long, at all times.

For a Safe Visit Check park publications for regulations and safety precautions. Be alert for ticks and chiggers. Use insect repellent. Avoid the park's two venomous snakes, the timber rattler and the northern copperhead. Federal law protects all animals and plants in the park. Do not disturb or kill them. Do not feed wildlife. If you have questions about any activity, check at the visitor center or ask a ranger.

Lodging and Services The Lodge at Mammoth Cave has rustic cabins, hot shower, coin laundry, food services, and a gift shop. Open spring to fall. For more information or reservations, go to

Find public amenities in the Caver's Camp Store and post office. For privately owned caves and services outside the park, contact Cave City Convention Center.

Source: NPS Brochure (2017)


International Biosphere Reserve — September 26, 1990
World Heritage Site — October 27, 1981
Mammoth Cave National Park — July 1, 1941 (established)
Mammoth Cave National Park — May 22, 1936 (minimum park area accepted for administration)
Mammoth Cave National Park — May 14, 1934 (minimum park area)
Mammoth Cave National Park — May 25, 1926 (authorized)

For More Information
Please Visit The
Link to Official NPS Website

Brochures ◆ Site Bulletins ◆ Trading Cards expand section


A privilege--a duty--an opportunity for Kentucky (1920s)

A Protocol for Monitoring Cave Crickets (Hadenoecus subterraneus) at Mammoth Cave National Park: Version 1.0 NPS Natural Resource Report NPS/CUPN/NRR-2015/934 (Kurt Lewis Helf, Tom Philippi, Bill Moore and Lillian Scoggins, March 2015)

A Report on the Monitoring Avian Productivity and Survivorship Program (MAPS) in Mammoth Cave National Park: 2004-2007 NPS Natural Resource Report NPS/CUPN/NRTR-2009/175 (Bill Moore, February 2009)

Annotated Checklist of the Vascular Flora of Mammoth Cave National Park, Mammoth Cave, KY (Landon McKinney, 2012)

Cave and Karst Management Plan/Environmental Assessment, Mammoth Cave National Park, Kentucky (July 2019)

Cave and Karst Resources Summary: Mammoth Cave National Park, Kentucky (Limaris Soto and Dale L. Pate, March 2016)

Checklist of Birds (Gordon Wilson, 1968)

Checklist — Mammals (undated)

Cultural Landscape Report: Core Visitor Center Area, Mammoth Cave National Park, Kentucky (Wiss, Janney, Elstner Associates, Inc., John Milner Associates, Inc. and Liz Sargent, November 2015)

Cultural Landscape Report: Mammoth Cave Historic District, Mammoth Cave National Park, Kentucky 100% Draft (Panamerican Consultants, Inc., Wiss, Janney, Elstner Associates, Inc. and Liz Sargent, March 2021)

Cultural Resources Management in Mammoth Cave National Park: A National Park Service/Kentucky Heritage Council Cooperative Project Summary (Bruce J. Noble, Jr., ed., 1991)

Cumberland Piedmont Network Ozone and Foliar Injury Report

Ozone and Foliar Injury Report for Cumberland Piedmont Network Parks: Annual Report 2008 NPS Natural Resource Data Series NPS/CUPN/NRDS-2009/012 (Johnathan Jernigan, Bobby C. Carson and Teresa Leibfried, November 2009)

Ozone and Foliar Injury Report for Cumberland Piedmont Network Parks Consisting of Cowpens NB, Fort Donelson NB, Mammoth Cave NP and Shiloh NMP: Annual Report 2009 NPS Natural Resource NPS/CUPN/NRDS-2010/110 (Johnathan Jernigan, Bobby C. Carson and Teresa Leibfried, November 2010)

Cumberland Piedmont Network Ozone and Foliar Injury Report — Chickamauga and Chattanooga NMP, Mammoth Cave NP and Stones River NB: Annual Report 2010 >NPS Natural Resource Data Series NPS/CUPN/NRDS-2011/219 (Johnathan Jernigan, Bobby C. Carson and Teresa Leibfreid, December 2011)

Cumberland Piedmont Network Ozone and Foliar Injury Report — Little River Canyon National Preserve, Mammoth Cave NP and Russell Cave NM: Annual report 2011 NPS Natural Resource Data Series NPS/CUPN/NRDS-2013/578 (Johnathan Jernigan and Bobby C. Carson, November 2013)

Cumberland Piedmont Network Ozone and Foliar Injury Report — Carl Sandburg Home NHS, Guilford Courthouse NMP and Mammoth Cave NP: Annual Report 2012 NPS Natural Resource Data Series NPS/CUPN/NRDS—2014/676 (Johnathan Jernigan, Bobby C. Carson and Teresa Leibfreid, July 2014)

Cumberland Piedmont Network Ozone and Foliar Injury Report — Kings Mountain NMP, Mammoth Cave NP and Ninety Six NHS: Annual Report 2013 NPS Natural Resource Report NPS/CUPN/NRR—2015/1044 (Johnathan Jernigan, Bobby C. Carson and Teresa Leibfreid, October 2015)

Cumberland Piedmont Network’s Cave Meteorology Report for Mammoth Cave National Park: Annual Report 2009–2010 NPS Natural Resource Data Series NPS/CUPN/NRDS-2011/218 (Johnathan Jernigan and Bobby C. Carson, December 2011)

Ethnographic Overview and Assessment, Mammoth Cave National Park Phase III Final Report (Darlene Applegate and Kate Hudepohl, May 2021)

Final Master Plan: Mammoth Cave National Park, Kentucky (1976)

Foundation Document, Mammoth Cave National Park, Kentucky (June 2014)

Foundation Document Overview, Mammoth Cave National Park, Kentucky (June 2014)

General Management Plan, Mammoth Cave National Park, Kentucky (October 1983)

Geologic Resources Inventory Report, Mammoth Cave National Park NPS Natural Resource Report NPS/NRPC/GRD/NRR-2011/448 (T.L. Thornberry-Ehrlich, September 2011)

Geology of the Mammoth Cave National Park Area (HTML edition) Kentucky Geological Survey: Special Publication 7 (Ann Livesay, 1953; rev. Preston McGrain, 1962)

Historic Structure Report: Superintendent's Residence, Mammoth Cave National Park (Wiss, Janney, Elstner Associates, Inc., September 2013)

Hovey's Hand-Book of the Mammoth Cave of Kentucky (HTML edition) (Horace Carter Hovey, 1909)

Interpretive Prospectus: Mammoth Cave National Park, Kentucky (1995)

Inventory of Terrestrial Wild Mammals at Mammoth Cave National Park NPS Natural Resource Technical Report NPS/CUPN/NRTR-2013/741 (Steven C. Thomas, May 2013)

Junior Cave Scientist Activity Book (Ages 5-12+) (2016; for reference purposes only)

Long-Range Interpretive Plan, Mammoth Cave National Park (2004)

Long-Range Interpretive Plan, Mammoth Cave National Park (June 2022)

Mammoth Cave: A Hotspot of Subterranean Biodiversity in the United States (Matthew L. Niemiller, Kurt Helf and Rickard S. Toomey, extract from Diversity, Vol. 13, 2021)

Mammoth Cave: Official National Park Handbook 158 (David Rains Wallace, 1998)

Master Plan and Wilderness Suitability Study/Final Environmental Statement, Mammoth Cave National Park, Kentucky (1976)

Master Plan, Preliminary Draft, Mammoth Cave National Park (December 1970)

National Register of Historic Places Nomination Forms

Bransford Spring Pumphouse (Kelly Lally, June 1989)

Colossal Cavern Entrance (Kelly Lally, June 1989)

Crystal Cave District (Kelly A. Lally, June 1989)

Good Spring Baptist Church and Cemetery (Kelly A. Lally, June 1989)

Great Onyx Cave Entrance (Kelly A. Lally, June 1989)

Hercules and Coach #2 (Philip B. Hasting, January 27, 1975)

Joppa Baptist Church and Cemetery (Kelly A. Lally, June 1989)

Maintenance Area District (Kelly A. Lally, June 1989)

Mammoth Cave Baptist Church and Cemetery (Kelly A. Lally, June 1989)

Mammoth Cave Historic District (Kelly A. Lally, June 1989)

Mammoth Cave National Park Historic Resource Study (Kelly A. Lally, October 1, 1990)

Maple Springs Ranger Station (Kelly A. Lally, June 1989)

Old Guide Cemetery (Kelly A. Lally, June 1989)

Residential Area District (Kelly A. Lally, June 1989)

Salts Cave Archeological Site (H-4) (Steven O. Smith, December 24, 1974)

Superintendent's House (Kelly A. Lally, June 1989)

Three Springs Pumphouse (Kelly A. Lally, June 1989)

Natural Resource Condition Assessment, Mammoth Cave National Park NPS Natural Resource Report NPS/MACA/NRR-2021/2258 (Chris Groves, Autumn Singer, Lee Anne Bledsoe, Richard S. Toomey III, Katie Algeo and Cathleen J. Webb, May 2021)

New Ctenacanth Sharks (Chondrichthyes: Elasmobranchii: Ctenacanthiformes) From the Middle to Late Mississippian of Kentucky and Alabama (John-Paul M. Hodnett, Rickard Toomey, H. Chase Egli, Gabe Ward, John R. Wood, Rickard Olson, Kelli Tolleson, Justin S. Tweet and Vincent L. Santucci, extract from Journal of Vertebrate Paleontology, February 1, 2024)

Newsletter (The Flashlight): Jan-Feb 2003Mar-Apr 2003Jan-Feb 2004

Ozone Levels at Mammoth Cave National Park: An Investigation into the Potential Source Areas Affecting High Ozone Levels at the Park (Miguel I. Flores and Robert E. Dattore, undated)

Poster: Mammoth Cave National Park (2009)

Present and Future Water Supply for Mammoth Cave National Park, Kentucky USGS Water-Supply Paper 1475-Q (R.V. Cushman, R.A. Krieger and John A. McCabe, 1965)

Proceedings of Mammoth Cave National Park's Conference, October 5-6, 2000, Mammoth Cave National Park (2000)

Proceedings of Mammoth Cave National Park's 10th Research Symposium: Celebrating the Diversity of Research in the Mammoth Cave Region (2013)

Soil Survey of Mammoth Cave National Park, Kentucky (2010)

The Geology and Physiography of the Mammoth Cave National Park (Armin Kohl Lobeck, 1928)

The Road Inventory for Mammoth Cave National Park (January 2000)

Topographic Map: Mammoth Cave National Park & Vicinity, KY Scale: 1:24,000 (USGS, 1974)

Wilderness Study, Mammoth Cave National Park (March 1972)


Road Building in Mammoth Cave National Park (c1936)

Mammoth Cave National Park

Books expand section

Last Updated: 16-Feb-2024