Hueco Tanks, a cluster of low syenite mountains northeast of El Paso, has been a vital water stop in the desert for at least 10,000 years because its natural rock basins and springs held water in an arid basin. Many peoples used the site over time, including Desert Archaic inhabitants, Paleo-Indians, Jornada Mogollon, Apache, Jumano, Comanche, Kiowa, and Tiguas. It is especially significant for its extensive Native American rock art, particularly hundreds of mask paintings associated mostly with the Jornada Mogollon. The site also preserves frontier history, from an 1837 Kiowa siege to stagecoach use, ranching, and eventual protection as a historic site.