National Geographic : 1962 Apr
Grand Canyon of the Colorado slices 300 miles across northwest Arizona and bares some of the world's oldest visible rocks. Fifteen to 20 major rapids and hundreds of lesser ones challenge rivermen. Jet boats voyaged 350 miles from Lake Mead to Lees Ferry. Toroweap Overlook, in Grand Can yon National Monument, looks down 2,802 feet into the Colorado. Expe dition wives on rim patrol chose van tage points like Toroweap to look for trouble and flash mirror signals to their husbands, who answered with sandwriting on the beaches (page 561). Mooney Falls tumbles into a tur quoise pool near Havasupai Indian Reservation, which lies half a mile below the canyon rim. The peaceful Havasupai long ago withdrew into this rock-walled retreat. Havasupai children swim at three years.