NAVAJO BRIDGE, sometimes called Marble Canyon or Grand Canyon Bridge, is the only highway bridge crossing the turbulent Colorado for approximately a thousand miles–from Boulder Dam to Moab, Utah. An engineering accomplishment and an object of great beauty, it is 834 feet long, has a single arch with a span of 616 feet, and measures 467 feet between its floor and the surface of the river–about the height of a forty-story building. Since its completion in 1929 the bridge as superseded the old Lee’s Ferry nearby.
The Colorado River is the western boundary of the Navajo Reservation, largest in the United States.

Since the American Guide was published, a second bridge was built to withstand today’s traffic, the original bridge is now only open to pedestrians, and a visitor’s center replaced the rest area.

“After completion of the new bridge, the old rest area on the west side of the bridge was remodeled and expanded to include an interpretive center. On the Navajo Nation (east) side of the bridge, there is an area for Native American craft vendors. The Navajo Bridge Interpretive Center opened for business in April of 1997 and was dedicated on June 17, 1997.” Source: NPS Navajo Bridge Interpretive Center (visit link)