Devils Postpile National Monument

Devils Postpile National Monument - August 8, 2003

The Devils Postpile National Monument can be found in the mountains west of Mammoth Lakes, California. The general public is discouraged from actually driving out there; instead, there are a series of shuttles that one can take (for $7, which seems kind of high for what you get and where you go) out of the lodge and into the mountains.

The Monument is more than just a pile of rock. There is some forested land and Rainbow Falls associated with the Monument, or at least found on Monument land. The San Joaquin River, the John Muir Trail, and the Pacific Crest Trail (or PCT) run thru various portions of the Monument. From the Devils Postpile itself, it is an easy 2.5 mile walk down to Rainbow Falls; all in all, a lot of stuff to see and do in a small area.

But back to the actual Devils Postpile. Less than 100,000 years ago (that seems like an awful long time ago to me but, in actual geologic time, this is the equivalent to the blink of an eye), there was a volcanic eruption 2 miles upstream from the present Devils Postpile. As the lava cooled down, it contracted and formed the columns you can see in the picture above. Kind of cool, huh? It gets better.

About 20,000 years ago, give or take, glacier activity in the area carved some of the postpile away. This carving exposed the wall of columns, above. The columns are about 60 feet high. Some of the exposed columns collapsed, and became the rocks seen at the bottom of the remaining columns. I did not go up to the top of the columns, but apparently the glacier has "polished" the tops so it looks like a tile floor.