Triangle X Ranch in Moose, Wyoming — Ninety-seven horses graze in the wide-open pasture land of this dude ranch overlooking the Snake River and the northern extension of the Rocky Mountains. This river valley was explored extensively by the U.S. in 1803-06 during the Lewis and Clark Expedition. Horses first arrived in North America in the late 15th century, having been brought across the Atlantic by Spanish Explorers. Native Americans helped spread horses across the continent. The horses are very social, and their grazing mingles with the sound of passing geese in the early morning river fog. It's a day off from the Triangle X, and all 97 horses are free to roam and frolic from sunrise to sunset.