Devils Postpile National Monument – What is it and Where is it?

This image shows the pile of rocks and columnar basalt that looks like fence posts in the Devils Postpile national monument.America’s national parks never fail to disappoint in their beauty and unique opportunities to understand our natural, cultural and historical world just a little better.

We had never heard of Devils Postpile National Monument until we were in Yosemite National Park, so after exploring John Muir’s beloved park, we found our way to Mammoth Lakes California and down a winding mountain road into the canyon that is home to this small unit of the National Park Service.

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What is a Devils Postpile

Devils Postpile national monument near Mammoth Lakes CaliforniaIf you’ve seen Devils Tower National Monument in Wyoming or the movie Close Encounters of the Third Kind, you have a little bit of an idea of how the Devils Postpile looks. Devils Tower was a part of the closing scenes of Close Encounters, where the alien space ship landed.

Devils Postpile National Monument in CaliforniaThe Postpile began as a volcanic eruption about 80,000 years ago. The basalt lava cooled and split into perfectly symmetrical six-sided columns. Then a few thousand years later, the glaciers moved through and smoothed the top of the columns. The Basque sheepherders of the region thought they looked like fence posts, thus the name Devils Postpile.

This canyon is home to the Middle Fork of the San Joaquin River. The John Muir Trail and the Pacific Crest Trail cross through the valley. It is the definition of serenity and majesty.

Local miners wanted to blow up the postpile and make a dam in the river to support their interests, so activists persuaded President Taft in 1911 to declare it a national monument. After an addition of the Ansel Adams Wilderness in 1984, the park is now almost 800 acres.

Visitors center covered in snowHere’s a cute little tidbit: During WWII, resources were obviously tight for the National Park Service, but they needed a visitors center at the Devils Postpile. In 1938, the Sentinel Hotel in nearby Yosemite had burned. Some of the wood had been salvaged, so resourceful rangers from Devils Postpile took a wagon and team of mules to Yosemite, snagged the wood, and built a small visitors center in the park. That snug, recycled building still serves the park today.

Getting to Devils Postpile National Monument

Road to Mammoth Mountain californiaThis area of the Western Sierras gets about 400 inches (1,016 cm) of snow a year, therefore the narrow winding mountain road is closed until about mid-June and stays open to the first snowfall, usually late Sept.

The number of vehicles allowed on this road is limited. When you see it, you’ll know why. It’s super steep and very narrow. Parking spaces are limited at the bottom, so most visitors are required to arrive via a city bus, which can be accessed at the Mammoth Mountain Adventure Center in Mammoth Lakes.

Therefore, only about 100,000 people a year find their way to this park.

Climbing the Devils Postpile

Devils Postpile is located at about 7,500 ft above sea level. For flatlanders like us, just walking without breathing heavy is a miracle at this altitude, so climbing a dirt path up the back side of the Devils Postpile generated some significant huffing and puffing on our part. But we made it in about 20 minutes and we’re so glad we made the effort.

Devils Postpile National Monument

Take a look at how the glaciers smooth off the top of the posts. It’s very cool in real life. The rocks are so smooth.

So we scooted back down the trail, in love again with the wonders of Mother Nature and the brilliant idea that is America’s National Park System.

  Selfie at Devils Postpile National Monument

While in the Mammoth Lakes area, we suggest you stop in for a cup of coffee and some killer cupcakes at Stellar Brewing. It’s as beautiful and natural as everything else here in the High Sierras.

Ready to Hike the Sierras?