Antelope Canyon is near Page, Arizona. It is a tribal park of the Dineh (Navajo) Indians. The shifting sunlight changes the colors of the rock in this narrow slot canyon. The rocks are sandstone, and the canyon was carved out by rushing monsoon water from summer rains. You must have a permit or go with a guide, and they won't let you in if there is rain 11 miles upstream, because you might not get out alive. Some people didn't, and there is a memorial to them. The best time of year to go is June; monsoon rains start in July and last through September.