Mammoth Cave National Park guide · 1 min read
Summer or Winter: Touring a 54°F Cave
Inside Mammoth Cave, the air holds a steady 54 degrees all year long, so the temperature underground in July matches January.
That makes the cave a cool retreat when surface temperatures in summer can climb past 90 degrees. Near the entrances the temperature swings more, most noticeably in winter, so a light jacket is a good thing to pack for your tour.
A ranger-led tour is the only way to go inside Mammoth Cave itself, and these tours pass through the world's longest cave system. Depending on the route you choose, a tour can last anywhere from one to six hours. From the visitor center, the path slopes downhill to the Historic Entrance, where icicles often decorate the opening in winter. Along the way, guides also cover human history that reaches back more than 5,000 years.
Tours are scheduled across two seasons, summer and winter. Summer draws the biggest crowds and offers the most tours. Winter weather on the surface is colder and the pace slows, so there are fewer tours but many fewer visitors. Since the cave stays at the same temperature, a midwinter trip can feel very pleasant once you are underground.
Book ahead, because tours sell out, particularly in summer and on holiday weekends. A few tours have only a small number of spots, and the Wild Cave Tour tends to fill first. Reservations are handled through the park's website, which sends you to the booking system for each tour. Look at the current tour listings before you settle on a day.
