Selway-Bitterroot Wilderness, Protected wilderness area in Idaho County and Montana, United States

The Selway-Bitterroot Wilderness spans the Bitterroot Mountains on the Idaho-Montana border, covering parts of four national forests. Elevations run from 1,700 feet on the Lochsa River to 10,157 feet at Trapper Peak. High areas around the Bitterroot peaks are rugged alpine parkland, while lower slopes are covered by dense coniferous forest.

The Selway-Bitterroot Wilderness was designated in 1964 under the Wilderness Act, the same year the law created the National Wilderness Preservation System. It covers parts of four national forests: Bitterroot, Clearwater, Lolo and Nez Perce. Only a dirt road, the Magruder Corridor, separates it from the Frank Church-River of No Return Wilderness to the south; together with adjoining public land the two areas form a wild region of about five million acres.

The wilderness lies along the Bitterroot Range on the Idaho–Montana border, and the Lochsa and Selway rivers rise inside it, flowing west to meet at Lowell, Idaho, where they form the Middle Fork of the Clearwater River. The Magruder Corridor, a dirt road, separates it from the Frank Church–River of No Return Wilderness to the south; together with adjoining public land the two areas form a wild region of about five million acres.

The wilderness is entered on foot or horseback; the Magruder Corridor, a dirt road, separates it from the Frank Church–River of No Return Wilderness to the south. Trails climb from the Lochsa River at 520 m to Trapper Peak at 3,096 m, so plan for snow at high elevations and dense conifer forest below.

The wilderness holds one of the largest elk herds in the United States and a healthy population of bighorn sheep. It is also one of the areas used to reintroduce wild packs of the grey wolf. Trapper Peak, at 10,157 feet (3,096 m), is the highest point, while the Lochsa River drops to 1,700 feet (520 m).