Mount Holmes is a 7,998-foot summit in the Henry Mountains of southern Utah, rising in a dry, sparsely settled landscape west of Glen Canyon National Recreation Area. Its runoff reaches tributaries of the Colorado River, impounded nearby as Lake Powell. The mountain is closely linked to the scientific exploration of the Henry Mountains in the 1870s, when geologist Grove Karl Gilbert surveyed the range and later published his landmark study on its igneous intrusions, introducing the term laccolith. Around 1878, Gilbert named the summit for artist and scientist William Henry Holmes. The area remains a cold semi-arid environment with little annual precipitation.