Steep descent into a 7000 year-young lava tube cave, reaching down three levels, with large icicles and and underground frozen lake on the lowest level. The cave was formed by volcanic gas bubbling through liquid lava dunging the last eruption of a Modoc volcano, and connects underground to the western side of Medicine Lake Road (highway 49).
Warning: None of the many caves here have any signage or guidance, many are long with multiple confusing branches, narrow crawl/climbing sections, sudden deep drops, loose rock, water and ice underground. Only teams of experienced cavers with the right equipment should attempt exploration.