Most caves in the Monument can be explored anytime without a reservation. Fern Cave, however, is closed for resource protection reasons and is open to visitors by ranger-guided tour only.  The entrance area is not open to the public at any time other than during a ranger-guided tour. The exceptional rock art and sensitive biotic environment in Fern Cave are among the reasons that only guided tours are allowed here.

The tour is offered on Saturdays at 2:00 p.m. from May 15th through October 31st, weather and road conditions permitting.

Tour Reservation Procedures & Requirements:

• Only one tour per Saturday
• Reservations are required and in high demand
• The tour is limited to 6 visitors per tour and lasts approximately 1 hour.
• Reservations can be made up to 3 weeks in advance by calling the Visitor Center, during operating hours only, at 530-667-8113.
• Participants are required to confirm their reservation the day before the tour by telephone or coming to the Visitor Center in person.
• All unconfirmed participant slots can be given away to the next inquiring party during open Visitor Center hours the day of the tour.
• Due to the sensitivity of this cave, children must be at least 12 years of age and accompanied by an adult.
• The tour requires climbing down a slanted ladder and negotiating sections of steep, slippery floor. Each member of the party must be able to do so safely.
• Closed-toed shoes with good traction and long pants are highly recommended.
• Participants should bring their own light sources for the tour. Headlamps, or a flashlight that can be placed in a pocket while climbing the ladder, are the best choices for lighting.