Boise Bar Campsite

Boise National Forest is a National Forest covering 2,203,703 acres (8,918.07 km2) of the U.S. state of Idaho. Created on July 1, 1908, from part of Sawtooth National Forest, it is managed by the U.S. Forest Service as five units: the Cascade, Emmett, Idaho City, Lowman, and Mountain Home ranger districts.

The Idaho Batholith underlies most of Boise National Forest, forming the forest's Boise, Salmon River, and West mountain ranges; the forest reaches a maximum elevation of 9,730 feet (2,970 m) on Steel Mountain. Common land cover includes sagebrush steppe and spruce-fir forests; there are 9,600 miles (15,400 km) of streams and rivers and 15,400 acres (62 km2) of lakes and reservoirs. Boise National Forest contains 75 percent of the known populations of Sacajawea's bitterroot, a flowering plant endemic to Idaho.

The Shoshone people occupied the forest before European settlers arrived in the early 19th century. Many of the early settlers were trappers and prospectors before gold was discovered in 1862. After the 1860s Boise Basin gold rush ended, mining of tungsten, silver, antimony, and gold continued in the forest until the mid-twentieth century. Recreation facilities include over 70 campgrounds, whitewater and flatwater boating, cabin rentals, and 1,300 miles (2,100 km) of trails for hiking, biking, horseback riding, and motorized off-road vehicle use. The Forest Service has an objective to maintain timber, range, water, recreation, and wildlife for multiple use and sustained yield of its resources.