Cinder cones erode easily and their scars are slow to heal. In 1973, Sunset Crater was closed to climbing after 2-foot-wide trails had eroded into 60-foot-wide swaths, and tons of cinder were shoveled back up the cone to fill hip-deep trenches. Scars remain visible, and plants will eventually return where cinders are left undisturbed, but walking in barren areas dislodges soil particles forming between the cinders. In 1928, Flagstaff residents stopped a movie company from dynamiting Sunset Crater, and where cinder cones are not protected they can be dismantled for building and landscaping materials. Human activities can level a mountain almost as fast as nature can create one.