Mammoth Cave is a major attraction year round, but be sure to bring a jacket when you visit as the caves’ interiors are cool regardless of the season. Summer is the most popular time to visit the caves and explore the rest of the park because of the temperate weather outside, but be prepared for a wait for some tours. The cooler days of spring and fall make them quieter times to arrive. Springfest in Old Louisville offers food trucks and local artwork in May. In late fall and winter, you’ll have much of the park to yourself, and September brings the Ten-Tucky Festival in Louisville, a series of plays by local professionals.