Cavern Trail

The Cavern Trail at Lewis and Clark Caverns State Park combines a strenuous hillside approach with a guided underground tour through Montana most spectacular limestone cave system, forming a loop that includes both surface and subterranean travel. The guided cave tour portion descends through chambers decorated with an extraordinary variety of dripstone formations: stalactites, stalagmites, helictites, flowstone curtains, cave popcorn, and rare cave coral that developed over hundreds of thousands of years as mineral-laden water slowly deposited calcium carbonate.

The cave maintains a constant temperature near 48 degrees Fahrenheit year-round, making a light jacket essential even in midsummer. The guided tour lasts approximately two hours and covers roughly a mile of underground passage through chambers ranging from tight crawlways to cathedral-sized rooms. Rangers lead small groups and provide detailed interpretation of speleothem formation, cave ecology, and the discovery history of the caverns. The approach trail to the cave entrance climbs steeply up a dry hillside above the Jefferson River, providing excellent views of the river valley and the Tobacco Root Mountains before ducking underground. Visitors exit through a lower portal and walk the remaining surface trail back to the visitor center, completing the loop. This is the longest guided cave tour operated by Montana State Parks.