The Teton Range is a mountain range of the Rocky Mountains in North America. A north-south range, it is mostly on Wyoming's eastern side of the Idaho state line. It is south of Yellowstone National Park. Most of the east slope of the range is in Grand Teton National Park. Early French Voyageurs used the name les trois tétons (the three nipples). It is likely that the Shoshone people once called the whole range Teewinot, meaning "many pinnacles".