The Secret Cave — Clyde McCulley

This is the last book of the Panther Creek Mountain series.The kids have an overnight campout in the Secret Cave. A panther tries to claw its way into the cave to attack them.Later, the neighbors on the ridge hear a terrible sound during the night, one like they have never heard.The old mountain men say it sounded like Big Foot. The kids think they must try to track it down. They might have a new visitor to their cave!!!