Mustang horses are probably the most well known wild horse in the United States. The name "Mustang" is derived from the Spanish words "mesteсo" or "monstenco" which is synonymous for "stray", "ownerless" or "wild." Mustangs come from domestic horses which reverted to a wild state after becoming separated from their human caretakers. They currently roam primarily on public land in the southwestern United States of Utah, Wyoming, Colorado, Idaho, Montana, Oregon, California, Arizona and New Mexico, but mostly in Nevada, where the majority of the country's remaining feral horse population resides. The Mustang is often called "The Symbol of the American West" and is known for their rugged endurance. Other names you may hear are: American feral horse, Range horse, Indian Pony, Cayuse Pony, American Mustang, Spanish Mustang, meste'os and BLM horse, which refers to the U.S. Bureau of Land Management that oversees their protection and adoption.