Tahquitz Peak

Tahquitz Peak is a granite, 8,846-foot-tall rock formation located on the high western slope of the San Jacinto mountain range in Riverside County, Southern California, United States, above the mountain town of Idyllwild. Tahquitz has a steep approach hike, leading to a roughly 1000-foot face. Tahquitz, which can refer to both the rock outcrop and the outcrop's parent peak, is a popular hiking destination to the fire lookout station and the rock climbing area.

The Yosemite Decimal System, widely used in North America to classify hiking and climbing routes, was developed into its modern form at Tahquitz Peak.

Source: Wikipedia