Craters of the Moon Crater Trail

Craters of the Moon National Monument in Southern Idaho is a vast ocean of lava flows, with scattered islands of cinder and splatter cones created by volcanic activity 15,000 years ago. Over 618 square miles, this surreal field displays the strange geography that can be caused by significant eruptive activity.

Most interesting is a series of caves created by lava tubes that guided molten magma up to the surface, where it bubbled and formed this amazing landscape. When the lava flow stopped, deep tubes were left behind, reaching to the source of the magma. Over the millennia, many of the tubes sealed up and collapsed, but some still remain, extending hundreds of feet below the surface of the park.

The three main caves (Indian Tunnel, Boy Scout Cave, and Beauty Cave) can be easily accessed by following Caves Trail, and are very close to the Cave Area parking lot.

Indian Tunnel is the largest of the caves, with multiple collapses that create skylights. Boy Scout Cave is especially interesting as it has a 2 foot crawl space that extends 15 feet, forcing you to scramble underneath to get out the other side. Beauty Cave is a 300-foot long tunnel, accessible via a scramble down a large slope of rocks.

Safety Note: Watch your step and your head – the caves are cold and dark, and it is very easy to slip on the pools and columns of ice. There are also many precarious, large icicles hanging from the ceiling.