The Hood River, formerly known as Dog River, is a tributary of the Columbia River in northwestern Oregon, United States. Approximately 25 miles (40 km) long from its mouth to its farthest headwaters on the East Fork, the river descends from wilderness areas in the Cascade Range on Mount Hood and flows through the agricultural Hood River Valley to join the Columbia River in the Columbia River Gorge. It rises in three separate forks on the north side of Mount Hood, within the Mount Hood Wilderness in Hood River County which is approximately 55 miles (89 km) east of Portland.