Half Dome -
Half Dome is a granite dome in Yosemite National Park, located in northeastern Mariposa County, California, at the eastern end of Yosemite Valley — possibly Yosemite's most familiar rock formation. The granite crest rises more than 4,737 ft above the valley floor.
One of the most stunning features is this 40-foot-long sliver of granite on Half Dome, named the Thank God Ledge. It's the only way to get beyond the Visor, a massive roof that looms over the Regular Northwest Face route. Most people crawl, there are several people who prefer to walk it, face out, since that’s “cooler.” It takes only about 30 seconds to make it across the ledge, and technically requires no climbing skills, but staring down at 1800 feet in the air isn't everyone's cup of tea.
Half Dome is nearly as whole as it ever was. The impression from the valley floor that this is a round dome which has lost its northwest half is an illusion. From Washburn Point, Half Dome can be seen as a thin ridge of rock oriented northeast-southwest, with its southeast side almost as steep as its northwest side except for the very top.
Although the trend of this ridge, as well as that of Tenaya Canyon, is probably controlled by master joints, 80 percent of the northwest "half" of the original dome may well still be there.
Half Dome was originally called "Tis-sa-ack," meaning Cleft Rock in the language of the local Native Americans. Tis-sa-ack is also the name of the fourth route on the formation, ascended by Royal Robbins and Don Peterson over eight days in October 1969. Tis-sa-ack is the name of a mother from a native legend. The face seen in Half Dome is supposed to be hers. Tis-sa-ack is the name of a Mono Lake Paiute Indian girl in the Yosemite Native American legend. John Muir referred to the peak as "Tissiack". In 1988, Half Dome was featured on a 25 cent United States postage stamp. An image of Half Dome, along with John Muir and the California Condor, appears on the California State quarter, released in January 2005. Starting October 2010, an image of Half Dome is included on the new revised California drivers license in the top right-hand corner. Half Dome is also an element or inspiration of various company and organization logos, including that of The North Face, Sierra Designs, & Mountain Khakis outdoor product companies, the Sierra Club environmental group and the Sierra Entertainment game studio..