Mahpahpahazhhah

Mahpahpahazhhah is a recorded name for the Sun River, which leaves the Rocky Mountains and flows east to the Missouri at the Great Falls. Its valley opens from the mountain front into the northern plains. The river is also known by the name Nataeosueti, rendered as Medicine or Sun River. In 1806 Meriwether Lewis passed near its junction with the Missouri on his return journey across the continent.