Daredevil Nik Wallenda completed a historic high-wire walk on a 2-inch (5-cm) steel cable over the Grand Canyon on Sunday and was greeted by wild cheers after his hair-raising stunt.Wallenda, the self-described "King of the High Wire," took 22 minutes and 54 seconds to walk 1,400 feet across the crimson-hued canyon with just a distant ribbon of the Little Colorado River beneath him. The event was broadcast live around the world.Wallenda, the first person to cross the canyon, made the walk without a tether or safety net.