The Hualapai's million acres (404,685 hectares) of land border about 100 miles (161 kilometers) along the western rim of the canyon (download a printable map of the Grand Canyon).
The Skywalk will be accessible through Grand Canyon West, the tribe's once-humble tourist destination.
Although Grand Canyon National Park along the south rim sees about four million tourists a year, until recently Grand Canyon West hosted only about 125,000 visitors.
To help bolster their numbers, the tribe agreed to build the Skywalk, which will eventually be joined by a three-story visitors' center, including a restaurant with patio seating along the canyon.
Mark Johnson, of Las Vegas-based MRJ Architects, has been working on the Skywalk for about three years, beginning with a lengthy design phase.
"There really is no building type for this," Johnson said.
He and a team of tribal consultants, engineers, and geologists started with the idea to build a single, straight walkway that would have stuck out from the canyon wall like a diving board.
They moved through several more design concepts before settling on a U-shaped walkway.
Sometime before opening day in March, the behemoth structure will be rolled out at a rate of half an inch (1.3 centimeters) a minute on tracks while concrete weights anchor the back.
When it's in place, the Skywalk will be anchored to giant poles drilled 40 feet (12 meters) into the canyon wall. Only 120 people will be allowed on the walkway at a time.
Johnson says the rock wall, not the walkway's design, is the wild card that could determine the Skywalk's life span.
At that height, the wall is made of 350-million-year-old limestone—porous material that is highly prone to erosion.
Geologists have a simple explanation for the formation of the Grand Canyon: the Colorado River cuts down through the rock, and the canyon's sides fall in (watch related video of rafting along the Colorado River).
Periodic rockfalls are an accepted and unpredictable reality. Johnson said there's no way to tell whether the part of the canyon that will support the Skywalk will last a hundred years or a thousand.
Delores Honta, a Hualapai tribal member from Peach Springs, doesn't give it very long.
"My prediction will be about 15 or 20 years," she said. "Our ground is very dry. It will not stay together. You're drilling holes and letting hot and cold air into it."
Several locals say that, while they are excited for the increased revenues from tourism, they're also leery of actually touring the Skywalk.
Jeanna Kay, a real estate agent in the neighboring community of Dolan Springs, hopes the project will give area land prices a boost.
But, she said, "I tell everybody, if you see me on the Skywalk, call 911."
Allison Raskansky, president and CEO of Destination Grand Canyon, said her company's efforts to promote Grand Canyon West and the Skywalk have shown promising early success.
"In the one year we've been marketing, we've more than doubled [visitor] traffic," she said.
Raskansky said the idea is to follow an existing Hualapai land-use plan to keep all the development modest and earthy.
The visitors' center will be made from native rock, she pointed out, and "there will never be a McDonald's."
But Hualapai member Honta, who at age 70 is considered a tribal elder, thinks the development is already going too far.
"I feel that they're tearing down our ground," she said. "It's a very sacred ground to us."
Honta says Native American soldiers killed in past conflicts were entombed in caves throughout the area. But the builders don't know where those burial grounds are.
"They don't know much about what's here, and one day they might run into them," she says.
Bravo, Grand Canyon West's operations manager, acknowledges that it took quite a bit of convincing to get a majority of the tribal elders to endorse plans for the Skywalk, and the project had to pass muster with the Hualapai Department of Natural Resources.
But now that it's under way, the project's backers say they're excited to have a chance to offer an experience that will be unique the world over.
"It should be scary, but it should be really a feeling of floating out there," Johnson, the architect, said. "It's going to keep your attention."
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