Mammoth Lakes Blue Diamond Nordic Routes

Get out your snowshoes and cross country skis and explore the Inyo Craters, Obsidian Dome, the Earthquake Fault, and the Knolls! The Sierra Club and the U.S. Forest Service partnered and reestablished the historic ungroomed Blue Diamond Nordic ski and snowshoe routes in the Inyo National Forest. Just look for these big blue diamonds on the trees.

In 1981, before the Scenic Loop Road was constructed, the Young Adult Conservation Corp. (YACC) joined forces with the Forest Service to establish twenty-five miles of Nordic trails by placing Blue Diamond markers in trees along designated routes in the Mammoth area and Obsidian Dome.

Blue Diamond Route


More than two decades later, cross-country skiers participating in Sierra Club Winter Outings noticed that many of the Blue Diamond markers were missing or in disrepair, making it very difficult to follow these routes. Local Sierra Club leaders wondered, “Shouldn’t these old trails be preserved?”

Blue Diamond Marker


For three years, Sierra Club volunteers were busy painting new metal Blue Diamonds and refurbishing the old ones. Out in the forest, these volunteers scaled tall ladders to attach the new diamonds to trees and to repaint faded diamonds already on the routes. To date, approximately twelve miles of the old routes have been restored.

Blue Diamond Height on Tree


Range of Light Group hopes everyone will enjoy and explore the Forest using this map. We invite other out-door enthusiasts to join us in sustaining the project. For more information contact

Have fun!