The valley extends approximately 95 miles (160 km) from Lost Trail Pass in Idaho, where it is narrow, to a point near the city of Missoula along I-90 where it is wider and flatter. To the west is the Bitterroot Range and its large Selway-Bitterroot Wilderness Area, and to the east is the smaller Sapphire Mountains and their Anaconda-Pintler Wilderness Area. The Bitterroot Range has steep faces, deep canyons, is heavily forested, and is within the Bitterroot National Forest. The Sapphire Mountains are more rounded, drier, and much less forested.
The southern end of the valley is split into the East and West Forks of the Bitterroot River, and the northern end has the confluence of the Bitterroot River with the Clark Fork River. Connecting into the west side of the valley are numerous deeply carved granite canyons, including scenic Blodgett Canyon and Lolo Creek's canyon.
Highway 93 runs through the center of the valley, exiting to the south over 7014 foot (2140 m) Lost Trail Pass. U.S. Highway 93 is the main travel choice through the Bitterroot Valley but East Side Highway also runs through the valley, being much less traveled.
Hamilton, the largest town and the county seat of Ravalli County, is located at 46°14.8'N and 114°09.6'W at an elevation of 3570 ft (1090 m) with a population of 4,000. Business opportunities within these cities include manufacturing, agriculture, craft breweries, wineries, recreational services, and many entrepreneurs.
In early September 1805, the Lewis and Clark Expedition crossed Lost Trail Pass from present-day Idaho in order to connect with the overland route through the Rocky Mountains. Passing down Camp Creek and the East Fork, they followed the Bitterroot River northward to the point where it connects with the Nez Perce Trail and Lolo Creek. Before continuing their difficult journey to the west, they named their camp Traveler's Rest. Returning to this site in early July of the following year, they split their Corps of Discovery, furthering their explorations both to the northeast (Lewis) and to the south (Clark).
The first 'white' settlement in the valley was the founding in 1841 of St. Mary's Mission, near present-day Stevensville, by Father DeSmet. Fort Owen was established nearby in 1850, and difficult relations occurred between the white settlers and the Salish until 1891, when the native tribes were relocated to the north. In 1877 Chief Joseph and the Nez Perce tribe passed south through the Bitterroot Valley, fleeing the U.S. Army. They exited the East Fork via Gibbons Pass, near where they fought at the Battle of the Big Hole.
The Bitterroot Valley had nearly a million apple trees in the early 1900s, and was one of the world's largest producers of MacIntosh apples at that time. Irrigation was provided by about 80 miles of canals. Although the Bitterroot Valley's orchards became less competitive with apple orchards in Washington State after hailstorms in 1922 and 1923, it is still home to one of the nation's largest cider orchards.
Settlement has continued since that time. The population of Ravalli County in the 2000 census was 36,070; 40,212 in the 2010 census. The major industries are ranching, agriculture, forestry, and tourism.
The Bitterroot Valley offers many recreational activities, including: hiking, backpacking, mountain biking, and rock climbing in the surrounding mountains; and birding and fishing along the Bitterroot River. The valley is popular with hunters, for big game, upland birds, and waterfowl.
- Go Northwest, LLC. Bitterroot Valley. Northwest Montana Travel Region. (1997-2014). 23 July 2014 Archived August 4, 2014, at the Wayback Machine.
- Distinctly Montana. "The Beautiful Bitterroot Valley." Wildlife & Parks. (2011). 24 July 2014
- Historic St. Mary's Mission, Inc. "Bitter Root Salish History." Historic St. Mary's Mission & Museum. (2004-2014). 23 July 2014
- Erickson, David (2017-09-04). "Cider apples could reclaim Bitterroot Valley's lost glory". Missoulian. Retrieved 2017-09-25.
- K Design Marketing Inc. "History of the Bitterroot Valley." Bitterroot Valley Chamber of Commerce. (2014). 24 July 2014[permanent dead link]