Little Devils Postpile

Little Devils Postpile is a rock formation featuring vertical basalt columns located along the Tuolumne River, several miles west of Tuolumne Meadows in the Sierra Nevada. The columns display distinctive hexagonal shapes that formed through the natural cooling process of ancient lava flows.

This formation emerged millions of years ago through volcanic activity when lava cooled and naturally contracted. The geometric columns resulted from this cooling process that worked over extended geological timescales.

The site represents a significant example of geological preservation within Yosemite National Park, drawing researchers and nature observers throughout the year.

The site can be reached via marked trails in Yosemite National Park, with the Pacific Crest Trail offering direct access from Tuolumne Meadows. Be prepared for rugged terrain and bring proper hiking gear and water.

The hexagonal basalt columns formed through a natural process where cooling lava fractured into regular geometric patterns. This structure mirrors the larger Devils Postpile located to the south, showcasing the same geological phenomenon on a smaller scale.

Location: California

Location: Tuolumne County

GPS coordinates: 37.90050,-119.41300

Latest update: December 12, 2025 17:42