United States Wilderness Areas, From the Gila in 1924 to the Arctic in 1980

Designated on June 3, 1924 in the Gila National Forest of New Mexico, this was the first area in the world to receive a formal wilderness designation. It spans 558,014 acres, and Whitewater Baldy at 10,895 feet is its highest peak. Every later stop on this trail follows the path it opened.

The Stanislaus National Forest area in California was first protected as the Emigrant Basin Primitive Area in 1931 and formally designated a wilderness on January 4, 1975. It shows the common route from a primitive area to wilderness law, and its 112,277 acres of glaciated terrain reach 11,570 feet at Leavitt Peak.

Established in 1940 and included in the National Wilderness Preservation System in 1964, this Oregon wilderness in the Wallowa Mountains is now 361,446 acres, the largest wilderness area in Oregon. It holds more than 60 named alpine lakes and four federally designated Wild and Scenic Rivers.

Formally designated under the Wilderness Act in 1964, this Montana wilderness is named for Bob Marshall, a forester and co-founder of The Wilderness Society who pressed the Forest Service in the 1930s to protect large roadless areas. It extends about sixty miles along the Continental Divide and covers just over one million acres.

Another 1964 designation, this time straddling Idaho and Montana, it protects roughly 1.3 million acres of the Bitterroot Mountains and the Selway River drainage. Its steep forested canyons support elk, mountain goat and gray wolf.

Established in 1964 under the Wilderness Act and named for the naturalist John Muir, it runs about ninety miles along the crest of the Sierra Nevada in California and encompasses roughly 652,793 acres, from near Mammoth Lakes south to Cottonwood Pass near Mount Whitney.

First designated in 1964 as the Minarets Wilderness, it was renamed and expanded in 1984, and now covers 231,533 acres. It contains the Ritter Range, including Mount Ritter, Banner Peak and the Minarets, and Thousand Island Lake, one of the largest backcountry lakes in the Sierra Nevada.

Designated by Congress in 1978 on the Montana and Wyoming border, it originally covered 904,500 acres and has grown to 937,102. It joins the granite Beartooth Mountains with the volcanic Absaroka Range, and Granite Peak at 12,807 feet is the highest point in Montana.

Created by an act of Congress in 1978 in the Flathead National Forest of northern Montana, it covers 286,700 acres and borders the Bob Marshall Wilderness, together forming part of the roughly 1.5 million acre Bob Marshall Wilderness Complex. Its Middle Fork of the Flathead River and grizzly habitat sit just west of the Continental Divide.

Established under the Alaska National Interest Lands Conservation Act of 1980, this wilderness lies entirely above the Arctic Circle in the Central Brooks Range and covers roughly seven million acres. It has no roads or maintained trails, and nearby Indigenous communities use it for subsistence hunting and traditional activities.