Diamond Peak is a distinctive double summit in the western Grand Canyon on the Hualapai Indian Reservation, rising steeply above the Colorado River at the mouth of Peach Springs Canyon where Diamond Creek enters the river. An erosional remnant of Cambrian Muav Limestone and Mississippian Redwall Limestone, it is a striking landmark in the lower canyon. The peak is closely linked to early Grand Canyon exploration: in 1858, Lieutenant Joseph Ives’s overland party, guided by Hualapai people, camped near Diamond Creek after leaving a damaged steamboat, becoming the first known European Americans to reach the river within the canyon. There, John Strong Newberry made the first geological observations and stratigraphic descriptions, and the peak and creek received their names.