Boyden Cavern

Boyden Cavern is a solution cave in Mesozoic marble in California’s Giant Sequoia National Monument, along the Kings Canyon Scenic Byway near the Kings River and just west of Kings Canyon National Park. Its entrance lies beneath the marble walls of the Portals of the Kings within Kings Canyon, described as the deepest river-cut canyon in the United States at about 8,200 feet deep. About 0.63 miles of the cave have been mapped. Inside are varied speleothems, including rare shield formations, as well as named chambers such as the Pancake Room, Upside Down City, Bat Grotto, and Drapery Room, ending at a small underground stream.

California · United States