The Mount Hood National Forest is 62 miles (100 km) east of the city of Portland, Oregon, and the northern Willamette River valley. The Forest extends south from the Columbia River Gorge across more than 60 miles (97 km) of forested mountains, lakes and streams to the Olallie Scenic Area, a high lake basin under the slopes of Mount Jefferson. The Forest includes and is named after Mount Hood, a stratovolcano. The Forest encompasses some 1,067,043 acres (4,318.17 km2). Forest headquarters are located in Sandy, Oregon. A 1993 Forest Service study estimated that the extent of old growth in the Forest was 345,300 acres (139,700 ha). The Forest is divided into four separate districts - Barlow (with offices in Dufur), Clackamas River (Estacada), Hood River (Mount Hood-Parkdale), and Zigzag (Zigzag).

In descending order of land area the National Forest is located in parts of Clackamas, Hood River, Wasco, Multnomah, Marion, and Jefferson counties.

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