The Grand Canyon Skywalk is a transparent horseshoe-shaped cantilever bridge and tourist attraction in Arizona near the Colorado River on the edge of a side canyon in the Grand Canyon West area of the main canyon.[1] USGS topographic maps show the elevation at the Skywalk's location as 4,770 ft (1,450 m) and the elevation of the Colorado River in the base of the canyon as 1,160 ft (350 m), and they show that the height of the precisely vertical drop directly under the skywalk is between 500 ft (150 m) and 800 ft (240 m).[2]
Commissioned and owned by the Hualapai Indian tribe, it was unveiled March 20, 2007, and opened to the general public on March 28, 2007. It is accessed via the Grand Canyon West Airport terminal or a 120-mile (190 km) drive from Las Vegas, which includes a 10-mile (16 km) stretch of dirt road which is currently under development. The Skywalk is east of Meadview and north of Peach Springs with Kingman being the closest major city.
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David Jin, an entrepreneur who had been involved with tourism and the Hualapai Nation for some time, had the idea of extending a platform out over the edge of the Grand Canyon. With the help of architect Mark Ross Johnson, that idea evolved into a rectangular walkway and eventually the "U"-shaped walkway that has now been constructed.
The overall Skywalk width is 65 feet (20 m). The Skywalk length extending out from the post supports closest to the canyon wall is 70 feet (21 m). The outer and inner 32-inch-wide (810 mm) by 72-inch-deep (1,800 mm) bridge box beams are supported by eight 32-by-32-inch (810 × 810 mm) box posts having four posts on each side of the visitor’s center, once completed. The eight posts are anchored in pairs into four large concrete footings that are in turn anchored to the bedrock by ninety-six 21⁄2-inch-diameter (64 mm) DYWIDAG (acronym pronounced Doo-Wee-Dag) high strength steel threaded rod rock anchors grouted 46 feet (14 m) deep into the rock.
The deck of the Skywalk has been made with four layers of Saint-Gobain Diamant low iron glass with DuPont SentryGlas interlayer. Deck width is 10 feet 2 inches (3.10 m). The Skywalk glass railings were made with the same glass as the deck, but fewer layers (two) bent to follow the walkway’s curvature. The glass railings are 5 feet 2 inches (1.57 m) tall and have been designed for high wind pressures.
The Skywalk deck was designed for a 100-pound-per-square-foot live load along with code required seismic and wind forces. The foundation can support the equivalent of 71 loaded Boeing 747 aircraft or an 8.0 magnitude earthquake within 50 miles (80 km).[3] Fine-tuning of the project occurred after a wind loading and pedestrian induced vibration analysis. Two tuned mass dampers were installed inside the outer box beam as well as one inside the inner box beam at the furthest extension of the Skywalk to reduce pedestrian footfall vibration. The walkway could carry 822 people that weigh 200 pounds (91 kg) each without overstress, but maximum occupancy at one time is 120 people.
The Skywalk was assembled on top of the canyon wall in line with its final placement and moved into final position by a jack and roll rig. The Skywalk infrastructure itself weighs a little over 1,000,000 pounds (450,000 kg) without counterweights but including the tuned mass dampers, railing hardware, glass rails, glass deck and steel box beams. At the time of roll-out, the Skywalk weighed approximately 1.6 million pounds. The process was completed in two days.
The Skywalk glass itself was manufactured and imported from Saint-Gobain Deutsche Glas (Kinon in Aachen) and Glas Döring in Berlin, Germany.
Structural design was provided by Lochsa Engineering out of Las Vegas, Nevada. Contractor is Executive Construction Management also located in Las Vegas, Nevada. Foundation design was aided by John Peck (Geologist), Aaron Hastings, P.E. of Arroyo Engineering Consultants, Inc. (Geotechnical Engineer), DJ Scheffler, Inc and Crux Subsurface, Inc.
Astronauts Buzz Aldrin and John Herrington attended the opening ceremony on March 20, 2007.
According to Hualapai officials, the cost of the Skywalk was $31 million.[4] Future plans for the Grand Canyon Skywalk complex include a museum, movie theater, VIP lounge, gift shop, and several restaurants including a high-end restaurant called The Skywalk Café where visitors will be able to dine outdoors at the canyon's rim. The Skywalk is the cornerstone of a larger plan by the Hualapai tribe, which it hopes will be the catalyst for a 9,000-acre (36 km2) development to be called Grand Canyon West; it would open up a 100-mile (160 km) stretch along the canyon's South Rim and include hotels, restaurants, a golf course, and a cable car to ferry visitors from the canyon rim to the Colorado River, which has been previously inaccessible.[4]
Opponents within the tribe view the project as disturbing sacred ground.[5] Supporters within the tribe counter that it is an opportunity to generate much-needed cash to combat serious problems that plague the small 2,000-resident reservation, including a 50% unemployment rate, widespread alcoholism, and poverty.[4] Other tribal members are happy with the Skywalk, but they have expressed concern over future over-development. They are also concerned about the potential lack of sustainability because the water used in both the development and the neighboring Grand Canyon National Park is not taken from the Colorado River but piped or trucked in from elsewhere.[4][6]
People outside of the tribe, including Arizona environmental groups and former National Park officials, have expressed concern about the project's obtrusiveness in the natural environment, considering it a defacement of a national treasure. Some have suggested it is ironic that the Hualapai had argued they were the best caregivers and stewards of the Grand Canyon, and yet decided to exploit it in this way.[4] Tribal leaders counter that the 4.5 million people a year who visit the National Park portion are already overburdening an area and, further, that the tribe needs financial income. The tribe's 1 million-acre (4,000 km²) reservation attracts approximately 200,000 visitors a year and charges for rim-side weddings and stunt jumps, including one by Robbie Knievel. The tribe made a foray into opening a casino but it has not been able to generate sufficient income.[4]
Access to the Skywalk can be made from Las Vegas, NV in the North or Kingman, AZ in the South, via Highway 93. Both routes converge (at CR 7/Buck and Doe Rd) near Diamond Bar Road, which was under construction as of Dec 7, 2009. At the time, Diamond Bar Road consisted of 10 miles (16 km) of an ungraded gravel and dirt road
Total cost to visit the attraction varies depending on how visitors arrive. In addition to a per person admission chart, visitors must pay for transportation to the remote site approximately 3 hours from Las Vegas, either via shuttle bus or for a travel permit from the Hualapai tribe. As of 2011, the final 14 miles (23 km) of road to the attraction were unpaved and travel guides caution visitors driving rental cars to verify that they are not violating rental agreements by traveling what may be considered "off-road".[3] In addition to admission and transportation charges, visitors may purchase photographs of their party at the gift shop.[7]