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Devils Postpile

Naturally, one of the main reasons to visit the Monument is the Postpile formation itself. 

Approximately 100,000 years ago, a lava flow erupted two miles upstream from the location of today's Monument.  As it flowed down the Valley, it eventually ran into an obstruction which served as a dam to the lava's path.  Pooling up to as deep as 400 feet behind the natural dam, the lava cooled.  Conditions were such that the lava--that was incredibly uniform in its mineral composition--cooled at a very slow rate.  As it cooled, it contracted and cracked, forming hexagonal columns.  80,000 years later, a glacier flowed through the same valley, overriding the formation and eventually revealing the sides and tops of the columns.  Glacial polish can still be seen today at the top of the formation.

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Rainbow Falls

Just a 2.5 mile walk from the Ranger Station, Rainbow Falls is the highest water fall on the Middle Fork of the San Joaquin river.

Plunging 101-feet down to the turbulent water below, the falls are aptly named for the many rainbows that appear in its mist throughout sunny summer days.

Visitors interested in a moderate day-hike can make a loop, embarking from the Ranger Station's trailhead to the Falls and returning via Shuttle Bus Stop 9, the Rainbow Falls Trailhead. The shuttle bus, which runs approximately every 20 or 30 minutes, can then return hikers to the Monument's Ranger Station from the Rainbow Falls trailhead.

Be sure to bring plenty of water and sunscreen for every member in your hiking group as the walk to the Falls is very hot, dry, and exposed.

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Minaret Lake lies in the heart of the Ansel Adams Wilderness.

The Postpile also serves as a starting point for many backcountry trips. Surrounded by both the Ansel Adams and John Muir Wildernesses, the Monument provides a portal to some of the most pristine backcountry destinations in the region.

Permits are required for all overnight trips in wilderness areas. While Devils Postpile National Monument can issue permits through a special arrangement with the Inyo National Forest, it is best for visitors planning on a backpack trip in the area to contact the Inyo's Wilderness Permit office directly. The most current regulations and trail quotas can be found by visiting the Inyo National Forest's website or by phoning the Inyo's Wilderness Permit Office at (760) 873-2485.