The Hoh River is a river of the Pacific Northwest, located on the Olympic Peninsula in the U.S. state of Washington. About 56 miles (90 km) long, the Hoh River originates at the snout of Hoh Glacier on Mount Olympus and flows westward through the Olympic Mountains of Olympic National Park and Olympic National Forest, then through foothills in a broad valley, emptying into the Pacific Ocean at the Hoh Indian Reservation. The final portion of the Hoh River's course marks the boundary between the south coastal segment of Olympic National Park and the Hoh Indian Reservation.