The Kootenai National Forest is a national forest located in the far northwestern section of Montana and the northeasternmost lands in the Idaho panhandle in the United States, along the Canada–US border. Of the 2.2 million acres (8,900 km2) administered by the forest, less than 3 percent is located in the state of Idaho. Forest headquarters are located in Libby, Montana. There are local ranger district offices in Eureka, Fortine, Libby, Trout Creek, and Troy, Montana. About 53 percent of the 94,272-acre (381.51 km2) Cabinet Mountains Wilderness is located within the forest, with the balance lying in neighboring Kaniksu National Forest.

Libby is a city in northwestern Montana, United States and the county seat of Lincoln County. The population was 2,775 at the 2020 census.