Sentinel Peak is a 6,592-foot-high (2,009 m) mountain summit located in the Olympic Mountains, in Jefferson County of Washington state. Rising in the center of Olympic National Park, its nearest higher neighbor is Mount Fromme, 1.42 miles (2.29 km) to the northwest. Sentinels Sister is a lower 6,301-foot-high (1,921 m) companion summit situated 0.65 miles (1.05 km) to the southwest. The two peaks stand as sentinels above the Dosewalips Valley and Hayden Pass, and were possibly named by an early expedition of the Seattle Mountaineers. Precipitation runoff from the peak drains to Hood Canal via the Dosewallips River.