Diamond Peak is the highest point in the Lemhi Range in the Rocky Mountains in Idaho. At 12,202 feet (3,719 m) above sea level, it is the fourth highest peak in Idaho. It is situated 34.5 miles (55.5 km) east of Borah Peak in the Lost River Range, opposite the Little Lost River valley. It is the highest point in the Caribou-Targhee National Forest. The closest higher peak is Mount Church, which is 31.8 mi (51.2 km) to the west.