From The National Geographic:
The all-glass, balcony-like “Skywalk”–shown in an illustration released this week–will extend over the edge of the Grand Canyon, 4,000 feet (1,200 meters) above the Colorado River. “The Skywalk will be an attraction unlike any other in the world,” said Sheri Yellowhawk, CEO of the Grand Canyon Resort Corporation. The company is building the bridge in the Hualapai Indian Reservation on the south rim of the canyon.