Thursday, January 30, 2014

Hike to top of strange Devils Postpile rocks

Devils Postpile formation
A massive collection of nearly perfect hexagonal columns of rock await day hikers on the Devils Postpile Trail in California.

The trail is an easy 0.9-mile round trip hike in Devils Postpile National Monument southeast of Yosemite National Park. The national monument protects the Devils Postpile formation – which this trails heads to the top of – and the 101-foot Rainbow Falls.

Because of the national monument’s high elevation in the Sierra Nevada Mountains, hikers can only visit from about mid-June to late October. With more than 400 inches of snowfall annually, the road to the monument usually closes the rest of the year.

Lava 600 feet deep
To reach the national monument, from Bishop, Calif., take U.S. Hwy. 395 north. Turn left/west on Calif. Hwy. 203 and drive through Mammoth Lakes. In about four miles, turn left/west onto Minaret Road, which heads up a steep mountain for a little more than four miles.

Drive past the Mammoth Mountain Main Lodge, parking alongside the road downhill from the Main Lodge and the Adventure Center. Walk west on the road to the Reds Meadow/Devils Postpile Shuttle, which is the only way to enter the national monument. Dogs that are well-behaved and muzzled are allowed on the shuttle bus.

Take the shuttle to stop 6 – the Ranger Station – in the national monument. The trailhead is near the station. The trail parallels the Middle Fork of the San Joaquin River, which is to the right and sports a gentle bend.

In 0.4 miles, the trail reaches the Devils Postpile. This 60-foot high wall sports some of the most perfect examples of columnar basalt in the world – if not mathematically flawless, it certainly is visually. About 55 percent of the columns are six-sided hexagons.

The postpile formed about 100,000 years when at least 600 feet of lava flowed south from what is now known as Pumice Flat. The thickness of the mass resulted in a slow, even cooling of the molten rock, resulting in long, symmetrical columns. The joints between the columns formed when the lava contracted as cooling. The columns average 2 feet in diameter with the largest at 3.5 feet.

Formation's topside
On the postpile’s northern side is a trail leading to the formation’s top; it can be scrambled up in about 15 minutes and is worth the effort.

A glacier during the last ice age smoothed and polished the postpile’s top, so when looking at your feet, you’ll see the shapes of each six-sided column. The top also offers a great view of The Buttresses, the monument’s oldest volcanic formation, to the west.

The national monument originally was part of Yosemite National Park, but mining interests forced its removal. Plans for a hydroelectric dam would have dynamited the postpile into rubble, but a counter-lobbying effort, which included John Muir, prevented the formation’s destruction. It became a national monument in 1911, protecting it from development.

While atop the postpile, make sure children are watched at all times and do not go near the edge.

After taking in your fill of the great views, return the way you came.

Find out about trail guidebooks available in the Hittin’ the Trail series.