Cathedral Peak is a granite mountain in Yosemite National Park’s Cathedral Range whose cathedral-like shape gave the range its name. Its form was created as glacial action in the Pleistocene carved and sharpened the mountain while its summit stood above surrounding ice as a nunatak. John Muir, during his first Sierra summer in 1869, admired its square mass, rooflike slopes, pinnacles, and spire, and linked its shape to joints in the granite. Geologically, it is Cathedral Peak Granodiorite, the youngest unit of the Tuolumne Intrusive Suite, formed about 83 million years ago. The peak also overlooks Cathedral Lakes and has long been important in Yosemite’s scenery, geology, and mountaineering history.