Text Box: Northern Rocky Mountains Introduction | Mountains and Batholiths | Glaciation | Resources
Most of the Northern Rocky Mountains province, or Northern Rockies, is in the northern half of Idaho and the western third of Montana; a small portion extends into northeastern Washington.  This is the largest of the Rocky Mountains provinces, and touches four other provinces, mostly the Great Plains to the east and the Columbia Plateaus to the south and west.  The province is only in contact with the Middle Rocky Mountains for a length of about 110 miles; therefore, although the Rocky Mountains extend from New Mexico to Alaska, the only place in the conterminous United States where the truly mountainous portions of the individual provinces are contiguous is along the 110-mile-long segment where the southeastern portion of the Northern Rockies province touches the northwestern corner of the Middle Rockies. 
The mountains of the Northern Rockies are generally not as high as those of the Middle and Southern Rockies.  Summit elevations are typically 6,800-7,800 feet and are more uniform in height than peaks in other parts of the Rockies.  The tallest peak in the province, and in Idaho, is Mt. Borah, also called Borah Peak (12,662 feet).  Many of the peaks form the Continental Divide within the province, which has a very circuitous path here.  It extends from the southeastern corner of the province northwestward forming the Idaho-Montana border for approximately 200 miles in the Beaverhead and Bitterroot ranges, then bends eastward off the border extending to just east of Butte, Montana; it then trends north-northwestward, passing slightly west of Helena, then nearly bisecting Glacier National Park, and finally extending into British Columbia, Canada.  Approximately 80 percent of the drainage of the Northern Rockies is westward, contrasting with the Southern Rockies in which only about one-third is westward; drainage in the Middle Rocky Mountains province is about equally divided between that toward the east and toward the west.  The main rivers that begin in the Northern Rockies include the Missouri River, which starts at Three Forks, 45 miles east of Butte (approximately half way between Butte and Bozeman), in southwestern Montana, at the confluence of the Madison, Jefferson and Gallatin rivers; the northward-flowing Middle Fork of the Salmon River, famous for its many rapids, for its designation as a National Wild and Scenic River, and for passing through the Frank Church-River of No Return Wilderness (the second largest unit of the National Wilderness Preservation System in the conterminous United States–second to the Death Valley Wilderness in California and Nevada); the Salmon River and Clearwater River, both of which flow into the Snake River; and the Pend Oreille River, Bitterroot River, and the Clark Fork.
There are several relatively large cities within the province, in marked contrast to the  lack of major cities within the Southern and Middle Rocky provinces.  Within the Montana portion of the province are Helena, the state capital; Missoula, the third most populous city in the state; and Butte and Bozeman.  The city of Coeur d’Alene is in northern Idaho near the western border of the province.  All these cities are on nearly flat basins between the mountainous portions of the province.  As in the other Rocky provinces, there are several smaller cities and towns, which mostly began in association with mining, in the more rugged sections. 
Northern Rocky Mountains Introduction | Mountains and Batholiths | Glaciation | Resources