English: The mouth of Cow Creek, where it flows into the Missouri. Sediments from Cow Creek form Cow Island a short distance downstream. Cow Creek provided a pathway from the northern Montana plains down through the Missouri Breaks to the Missouri River. Cow Island made crossing the Missouri easier. On the south side of the river a relatively short (4 to 6 miles) but steep climb up the reavines gained the Montana plains south of the Missouri. This pathway was used for centuries by migrating bison and nomadic Indians. Now migrating bison and nomadic Indians are gone, and Cow Creek and Cow Island are isolated portions of the remote Missouri Breaks.