Montana's Rivers, Lakes, and Waterfalls

Two of Montana’s largest rivers, the Missouri and Yellowstone, flow east of the Continental Divide. The Missouri is formed in southwestern Montana by the union of the Jefferson, Madison, and Gallatin rivers. It breaks through the mountains north of Helena in a deep gorge called the Gates of the Mountains. The Missouri River’s most important branches in Montana include the Sun, Teton, Marias, and Milk rivers, which flow into it from the north, and the Judith and Musselshell rivers, which enter from the south. The Yellowstone Rover flows more then 400 miles through southeastern Montana. It’s most important tributaries include Clark’s Fork, and the Bighorn, Tongue, and Powder rivers. Major rivers west of the Continental Divide include the Kootenai and the Clark Fork of the Columbia River. The Clark Fork’s chief branches are the Blackfoot, Bitterroot, Flathead, and Thompson rivers.


Montana is the only state drained by three river systems emptying into three different oceans. The Missouri-Mississippi system drains into the Atlantic, the Columbia empties into the Pacific, and the Nelson Saskatchewan flows into the Arctic. The belly St. Mary, and Waterton rivers empty into the Nelson Saskatchewan system.

Flathead Lake and Fort Peck Reservoir are the two larges lakes. Flathead Lake, located in northwestern Montana, covers 189 square miles. Fort peck Reservoir in northeastern Montana has an area of 383 square miles. Other large lakes include Hungry Horse, Canyon Ferry, and Tiber reservoirs. More then 1,500 other lakes lie throughout northern and western Montana. The rivers supply drinking water to upland waterfowl birds, small game and big game of all kinds.

Montana waterfalls include the Great Falls of the Missouri River near Great Falls, the Kootenai Falls near Troy, and Skalkaho Falls near Hamilton. Black Eagle Falls and Rainbow Falls form part of the series that make up the Great Falls. There are many areas that supply water to the wildlife only increases the chances that a guide or outfitter can help you with a successful guided hunting trip.