Three words: Varied, historic, magnificent. The Missouri and Yellowstone are the longest, and each have major tributaries draining from the Eastern Slope of the Continental Divide. So much U.S. history on both, going back to the Lewis & Clark expedition in 1804–1806. read more
The Yellowstone River, beginning in southwestern Wyoming, flows across the state into North Dakota, where it joins the Missouri. Smaller rivers and streams are commonplace, as well as alpine lakes, tundra and glacier ice in the higher elevations of the northern mountains. For a detailed look at the topography of Montana, view this topography map. read more