Mammoth Cave National Park

Mammoth Cave National Park protects the longest known cave system in the world, an almost unimaginable labyrinth of more than 400 mapped miles of passages, chambers, pits and underground rivers winding beneath the rolling hills and forests of south-central Kentucky. So vast that its full extent is still unknown, Mammoth Cave has earned recognition as a UNESCO World Heritage Site and an International Biosphere Reserve for its extraordinary geology and biodiversity.

Carved over millions of years by water dissolving the thick limestone of the region, the cave is a wonderland of grand avenues, towering vertical shafts, delicate gypsum formations, and rare cave-adapted creatures found nowhere else. Above ground, the park preserves the forested hills, the Green and Nolin rivers, sinkholes and springs of the karst landscape. With its world-record cave, guided tours into the depths, rich human history spanning thousands of years, and aboveground trails and rivers, Mammoth Cave is one of the great natural wonders of America.

Mammoth Cave National Park is famous for its ranger-guided cave tours, ranging from easy walks to strenuous, adventurous wild-cave crawls through the world’s longest cave system. Aboveground, the park offers more than 80 miles of hiking, biking and horseback trails through forested karst country, canoeing and kayaking on the Green and Nolin rivers, camping, fishing and birding. The combination of the extraordinary cave and the scenic surface landscape makes Mammoth Cave a premier destination for cave explorers, hikers, paddlers and nature lovers.

The cave stays a constant cool temperature year-round, so tours run in every season — summer is the busy peak, when reserving tours in advance is essential, while spring and fall offer milder surface weather, wildflowers or color, and smaller crowds. Winter is quiet, with the cave a refuge from the cold. The cave is rewarding any time; spring and fall are ideal for combining cave tours with the surface trails and rivers. Always reserve cave tours ahead, especially in summer.

Mammoth Cave has one of the longest records of human use of any cave on Earth — Native Americans explored and mined its passages for thousands of years, leaving remarkably preserved artifacts. In the early 1800s the cave was mined for saltpeter for gunpowder, then became one of America’s first tourist attractions, with enslaved guides like Stephen Bishop making famous discoveries. Established as a national park in 1941 and later a World Heritage Site and Biosphere Reserve, Mammoth Cave preserves both the world-record cave and its deep, layered human history.

Mammoth Cave formed over millions of years as slightly acidic groundwater dissolved the thick layers of ancient limestone beneath a protective caprock of sandstone, creating the vast, multi-level maze of passages, the world’s longest known cave system. The surrounding karst landscape — with its sinkholes, springs, disappearing streams and underground rivers like the Echo and Styx — reflects the same dissolving of the limestone. The combination of soluble limestone, a protective sandstone cap and abundant water created this extraordinary and still-growing subterranean labyrinth.

Mammoth Cave is renowned for its biodiversity, both above and below ground — the cave shelters more than 130 species, including rare and endangered cave-adapted creatures like the eyeless Kentucky cave shrimp, cavefish, blind beetles and bats, found nowhere else. Aboveground, the forests, rivers and karst host white-tailed deer, wild turkey, foxes, and a rich community of birds, while the Green River supports a remarkable diversity of fish and mussels. This exceptional life makes Mammoth Cave an International Biosphere Reserve and a haven for wildlife and biodiversity.

Mammoth Cave National Park is an International Biosphere Reserve of extraordinary biodiversity, protecting both a rich cave ecosystem — home to rare, endemic, cave-adapted species in one of the most diverse cave systems on Earth — and a surface landscape of forested karst, the Green and Nolin rivers (renowned for their freshwater mussels and fish), sinkholes and springs. The intimate connection between the surface and the cave makes water quality vital. Protecting the cave, the rivers and the karst forest sustains a globally significant and interconnected ecosystem.

Mammoth Cave holds a place of global and American significance as the longest cave on Earth, a UNESCO World Heritage Site, and a landscape with one of the longest histories of human use of any cave — from ancient Native American explorers to the enslaved guides who mapped its depths and the generations of visitors drawn to its wonders. Its world-record passages, its rich history and its extraordinary biodiversity make Mammoth Cave a treasured natural and cultural icon, one of the great wonders of the American landscape.

Mammoth Cave National Park is in south-central Kentucky near Cave City and Brownsville, off Interstate 65, about 90 miles south of Louisville and 30 miles northeast of Bowling Green. The park is free to enter, but cave tours (the main attraction) require tickets and reservations, especially in summer. The park offers a visitor center, ranger-guided cave tours, surface trails, river access, campgrounds and a lodge. Check the National Park Service for tour reservations, schedules and conditions well before visiting.

The National Park Service protects the world’s longest cave system, its rare cave life, and the surface forests, rivers and karst of Mammoth Cave National Park, a World Heritage Site and Biosphere Reserve. Visitors help by taking only guided tours into the cave, never touching formations or cave life, following decontamination steps that protect bats from white-nose syndrome, staying on trails, protecting the rivers’ and groundwater’s quality (vital to the cave), and packing out everything. Protecting the cave, the karst and the rivers sustains this globally significant and fragile ecosystem.

Cave tours range from easy to strenuous, with stairs, uneven footing, tight passages and total darkness — choose a tour matching your fitness and comfort, wear sturdy footwear and a light layer (the cave is cool), and follow ranger instructions closely; never enter the cave without a guide. Aboveground, watch footing near sinkholes and on river bluffs, wear a life jacket when paddling the rivers, carry water, and be mindful of ticks in summer. Respect the cave’s hazards, the karst terrain and the rivers.

The park is free to enter, but the cave may be entered only on authorized ranger-guided tours (tickets and reservations required). Never touch cave formations or wildlife; follow bat-protection decontamination rules. Stay on trails and back from sinkholes and bluff edges. Camp only in designated areas; follow river and fishing regulations and licensing. Pets are restricted (not allowed in the cave). Drones are prohibited. Collecting is prohibited. Pack out all trash. Check the National Park Service for tour reservations and current rules before visiting.

The towns of Cave City, Brownsville and Park City lie near the park, with the Green and Nolin rivers, the karst country of south-central Kentucky, and the city of Bowling Green nearby. Louisville is about 90 miles north and Nashville about 90 miles south. The region’s caves, rivers and rolling hills define the landscape. Mammoth Cave anchors a region of world-renowned caves and karst scenery, a centerpiece of an outdoor and cave-exploring adventure in south-central Kentucky.

Reserve a ranger-guided cave tour well in advance — especially in summer — and choose one matching your fitness, from easy walks to strenuous adventures, wearing sturdy shoes and a layer for the cool cave. Above ground, hike the forested karst trails, paddle the scenic Green River, and watch for the park’s rich wildlife. Never touch cave formations or skip the bat-protection steps, camp or stay at the lodge, and combine the world’s longest cave with the surface beauty of this World Heritage park.