Kasha-Katuwe Tent Rocks National Monument, New Mexico. "Kasha-Katuwe" means "white cliffs" in the native language of the Pueblo de Cochiti, nearby. The cone-shaped rock formations are the products of volcanic eruptions that occurred 6 to 7 million years ago, leaving deposits over 1,000 feet thick, which have subsequently eroded into tent-like shapes. The slot canyon is spectacular.