Montana Geography
With a land area of 145,552 square miles (376,978 km²) the state of Montana is the fourth largest in the United States (after Alaska, Texas, and California). To the north, Montana and Canada share a 545 mile (877 km) border. The state borders the Canadian provinces of British Columbia,Alberta, and Saskatchewan, more provinces than any other state. To the east, the state borders North Dakota and South Dakota. To the south is Wyoming and to the west and southwest isIdaho.
The topography of the state is diverse, but roughly defined by the Continental Divide, which runs on an approximate diagonal through the state from northwest to south-central, splitting it into two distinct eastern and western regions. Montana is well known for its mountainous western region, part of the northern Rocky Mountains. However, about 60% of the state is actually prairie, part of the northern Great Plains. Nonetheless, even east of the Continental Divide and the Rocky Mountain Front, there are a number of isolated “Island Ranges” that dot the prairie landscape.
The Bitterroot Mountains divide the state from Idaho to the west with the southern third of the range blending into the Continental Divide. Mountain ranges between the Bitterroots and the top of the Continental Divide include the Cabinet Mountains, the Missions, the Garnet, Sapphire, Flint Creek, and Pintlar ranges.
The northern section of the Divide, where the mountains give way rapidly to prairie, is known collectively as the Rocky Mountain Front and is most pronounced in the Lewis Range located primarily in Glacier National Park. Due to the configuration of mountain ranges in Glacier National Park, the Northern Divide (which begins in Alaska’s Seward Peninsula) crosses this region and turns east in Montana at Triple Divide Peak. Thus, the Waterton, Belly, and Saint Mary rivers flow north into Alberta, Canada, joining the Saskatchewan River and ultimately emptying into Hudson Bay.
East of the Divide, several parallel ranges march across the southern half of the state, including the Gravelly Range, the Tobacco Roots, the Madison Range, Gallatin Range, Big Belt Mountains, Bridger Mountains, Absaroka Mountains, and the Beartooth Mountains. The Beartooth Plateau is the largest continuous land mass over 10,000 feet (3,000 m) in the lower 48 states and contains the highest point in the state, Granite Peak, 12,799 feet (3,901 m) high.
Between the mountain ranges are many scenic valleys, rich in agricultural resources and rivers, and possessing multiple opportunities for tourism and recreation. Among the best-known areas are the Flathead Valley, Bitterroot Valley, Big Hole Valley, and Gallatin Valley.
