Half Dome is a granite rock formation in California’s Yosemite Valley that was named for its half-dome shape. Like many of the rock formations in Yosemite, including El Capitan, Half Dome was formed with the aid of glaciation, and the Half Dome rock is approximately 93 million years old.
Here is a description of some of the geology of Yosemite Valley from the National Park Service:
“Yosemite is a glaciated landscape, and the scenery that resulted from the interaction of the glaciers and the underlying rocks was the basis for its preservation as a national park. Iconic landmarks such as Yosemite Valley, Hetch Hetchy, Yosemite Falls, Vernal and Nevada Falls, Bridalveil Fall, Half Dome, the Clark Range, and the Cathedral Range are known throughout the world by the photographs of countless photographers, both amateur and professional. Landforms that are the result of glaciation include U-shaped canyons, jagged peaks, rounded domes, waterfalls, and moraines. Glacially-polished granite is further evidence of glaciation, and is common in Yosemite National Park.”
When the weather is permitting, travelers can drive a car or take a bus to Glacier Point, an area which offers stunning views of Half Dome and many of the granite formations in Yosemite Valley.
Country: United States
Half Dome stands in Yosemite Valley in Yosemite National Park, Mariposa County, California.
Mountain Range: Sierra Nevada
Height: 8,844+ feet / 2,695+ meters
First Ascent: October 1875 by George G. Anderson
Fun Fact: The most popular trail up Half Dome is the cable route, which has as many as 1,000 climbers a day when the weather is nice!