IN JANUARY, ARIZONAS Hualapai tribe, whose 2,000-person reservation covers 1,500 square miles along the Grand Canyon's south rim, is opening a glass-bottomed, horseshoe-shaped walkway that will jut 70 feet from the edge, 4,000 feet above the canyon floor. Located 200 miles west of the crowded lookouts of Grand Canyon National Park, the Skywalk at Grand Canyon West is expected to lure some 500,000 visitors annually, providing a boost to the Hualapai, whose unemployment rate hovers around 24 percent. "It's noiseless, it's going to blend with the environment, and it will allow people to see the canyon in a nonpolluting, nonmotorized, unobtrusive way," says Sheri Yellowhawk, CEO of the Hualapai's Grand Canyon Resort Corporation. But with a hotel, campground, and tramway in the works—and the tribe, as a sovereign nation, subject only to its own internal environmental assessments—conservation groups are less enthusiastic. "It's a Disneyland approach to one of the world's most glorious natural wonders," says Jo Johnson, co-director of the Boulder, Coloradobased nonprofit River Runners for Wilderness, which pushes for environmental protection along the Colorado. "I understand the tribe's need from an economic view, but the point should be to see nature on its own terms."