At the head of the valley in Yosemite National Park, as if on a pedestal, stands Half Dome, the most colossal and recognizable rock monument in the Sierra Nevada, smoothly rounded on three sides and a sheer vertical face on the fourth. Half Dome, which stands nearly 8,800 feet above sea level, is composed of quartz monzonite, an igneous rock that solidified several thousand feet within the Earth. Half Dome, is the remains of a magma chamber that cooled slowly and crystallized beneath the Earth’s surface. The solidified magma chamber was then exposed and cut in half by erosion, therefore leading to the geographic name Half Dome.

The Half Face of a Mountain