The Willamette National Forest is a National Forest

United States National Forest

National Forest is a classification of federal lands in the United States.National Forests are largely forest and woodland areas owned by the federal government and managed by the United States Forest Service, part of the United States Department of Agriculture. Land management of these areas...

 located in the central portion of the Cascade Range

Cascade Range

The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...

 of US state of Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

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It comprises 1,675,407 acres (2,618 mi², 6,780.13 km²) making it one of the largest national forests. Over 380,000 acres (694 mi², 1,540 km²) are designated wilderness

National Wilderness Preservation System

The National Wilderness Preservation System of the United States protects federally managed land areas designated for preservation in their natural condition. It was established by the Wilderness Act upon the signature of President Lyndon B. Johnson on September 3, 1964...

 which include seven major mountain peaks. There are also several National Wild and Scenic Rivers within the forest.