Tucked Inside A California Valley Lies A Breathtaking Waterfall With Dancing Rainbows And Cooling Mist

In the heart of the Sierra Nevada mountains in central eastern California is an evocative destination where light meets dark as colorful rainbows dance across cooling mists and the shadowy hues of volcanic rock. The appropriately named Rainbow Falls is a 101-foot waterfall in the middle of the Devils Postpile National Monument, and the two sites together embody the geometrical perfection that sometimes only nature is capable of achieving. You have to hike to reach Rainbow Falls, and many people choose to do so on a trail that takes you past the Devils Postpile, a surreal formation of 60-foot high hexagonal basalt columns formed by volcanic activity about 80,000 years ago. 

Initially, the postpile — named by 19th-century Basque shepherds who thought the columns looked like piles of wood posts — was a 400-foot deep molten lava lake, which cooled over time and as it did, started cracking along the joints seen in the columns today. Slow-moving but persistent glaciers eroded the area, revealing a landscape straight out of H.P. Lovecraft's "At the Mountains of Madness."

Rainbow Falls, just 2.5 miles away from Devils Postpile, were similarly formed by volcanic spewings and coolings, which is why you can see less dramatic but still impressive lines and geometric formations in the waterfall's rhyodacite cliffs. Rainbow Falls and Devils Postpile National Monument are just over 30 minutes from Mammoth Lakes, California's underrated year-round adventureland resort town, so this is an ideal destination for anyone looking to embark on an adventure in the Golden State's fascinating volcanic landscape.

The first rule about Rainbow Falls is you do not talk about Rainbow Falls. Actually, the first rule is to know how to get to Rainbow Falls. To keep the wilderness free of congestion and pollution, the National Park Service has instilled a seasonal almost-mandatory shuttle service that runs from Mammoth Lakes to the Devils Postpile National Monument. The shuttle typically operates from late June to early September, although its schedule depends on weather conditions. It runs every 20-45 minutes depending on the time of day and it goes from 7:30 a.m. to 7 p.m. Between 9 a.m. and 4:30 p.m., visitors should use the Mammoth Mountain Park Shuttle instead of the Reds Meadow/Devils Postpile one.

You can check the NPS website for information, as there are exceptions to shuttle use, such as those camping overnight or heading to the monument outside of shuttle operation times. The shuttle departs from Mammoth Mountain Main Lodge and you can buy tickets online at the Eastern Sierra Transit Authority website. At the time of writing, tickets for adults cost $15 and are $7 for kids aged 3-15. You can buy tickets on board or at the Mammoth Mountain Adventure Center, although it's recommended to reserve your seats if going over a holiday or busy weekend.

In 2025, the Forest Service is conducting major repairs on Reds Meadow Road, which leads to the Devils Postpile National Monument that's basically a mini Yosemite without the crowds. The shuttle schedule has been limited to Thursday through Sunday or just weekends, depending on the time of year. This also affects those visiting the area in the off-season. Check the Forest Service website for updates on road closures. This reconstruction is expected to be done by 2026.

Two trails lead to Rainbow Falls, both of which have different shuttle stops. The longer of the two is a 5-mile out-and-back trail that begins at the Devils Postpile Trailhead, which you can access via shuttle stop #6. The trail starts at the ranger station, where you'll have access to bathrooms and water stations, and you can stop at the Devils Postpile formation just .5 miles away. 

It's worth it to explore this geologic wonder, which you can see from below — where tectonic activity has cracked off piles of the columns — and from above, where you can see the smooth hexagonal floor that's actually the top of the formation. It's not just hexagons, by the way; pentagons and heptagons abound, too.

It's 2.5 miles from the ranger station to the waterfall, and the trail passes through forested and open areas burned by a 1992 wildfire (it also connects with the Pacific Crest Trail). It's another 1.5 miles to the Red's Meadow Resort, where you can pick up the shuttle and also a delicious milkshake. As a shorter alternative, you can begin the hike at the resort (shuttle stop #10) and do 3 miles total instead of 5 miles; note that this option bypasses Devils Postpile.

The best time to catch the waterfall's rainbow is mid-day, when the sun is the highest, and you can explore the falls from above and below to see for yourself if it's one of the world's most ethereal waterfalls. Although Rainbow Falls flows all year, it's most voluminous and colorful in June and July, which also means it's the most crowded then. To beat the crowds, consider going in the fall, earlier in the day, or on a weekday.