Nestled deep inside the Siskiyou Mountains, the caves formed as rainwater from the ancient forest above dissolved the surrounding marble and created a special marble cave system. The highly complex geology found on the Monument and Preserve contributes to the unusual and rare plants and animals found here. Experience the extensively decorated and adventurous "Marble Halls of Oregon."
Discover the Marble Halls of Oregon
Circle of Discovery
Did you know that northern California and southern Oregon are home to seven national park sites? Explore the Circle of Discovery!