The cliffs appear solid and motionless, but visible scars reveal a different story. In July 1983, a huge slab broke off the opposite cliff, leaving a buff-colored scar and tons of rubble at the base, and the entire event was over in moments. These canyons are not permanent scenery; many rockfalls have shaped their dynamic and evolving form. Dramatic facelifts like the 1983 rockfall are relatively rare, but frequent small piles of rocks on the roadway reveal the terrain’s volatile personality.