With only four inches of glass underfoot and a railing barely above elbow level to protect me from a powerful wind, I stepped out 4,000ft (1,200m) above the Grand Canyon yesterday, minutes after the new Skywalk platform was opened. Never have I covered such a short distance so slowly — or carefully.

The U-shaped platform, which extends 70ft over the edge of the canyon, is a $30 million (£15 million) feat of engineering designed to lure tourists from Las Vegas to a little-visited Native American reservation on the west rim of the Grand Canyon.

However, the three-hour journey from “Sin City” to the Hualapai reservation is not easy, and includes almost an hour of driving on a bone-jarring unpaved road.

The attraction itself stands on an almost-empty patch of desert land, with a visitors’ centre in the early stages of construction. The astronaut Buzz Aldrin made the “first walk” around the platform yesterday, after tribal leaders blessed it in a ceremony.

David Jin, the Chinese-American businessman who conceived and funded the project, managed only a cryptic statement about how he came upon the idea: “First there was a circle, then a square, then the U-shape.”

Mr Jin, who has described the Skywalk as the most magnificent monument on Earth, donated the structure to the Hualapai tribe, but will share in profits from the $25 entrance fee for the next 25 years.

The project has stirred controversy on the Hualapai Reservation; supporters say that it will create valuable jobs but opponents condemn it as a desecration of a sacred landscape.

“I felt wonderful, not exactly floating on air . . . but a vision of hope for the future,” Mr Aldrin, the second man to walk on the Moon, said after his stroll. The astronaut’s few steps marked the official inauguration of the project, whose backers hope that it will draw up to half-a-million paying visitors this year to the site, about 120 miles (190km) east of Las Vegas.

Out on air

-The Skywalk is a horseshoe-shaped steel-and-glass pathway cantilevered 70ft (20m) out over the Grand Canyon T

-he peach-coloured frame is bolted to the rim of the canyon and could support the weight of more than 70 Boeing 747s, according to engineers

-The walkway is paved with 90 tonnes of strengthened glass imported from Germany, and hangs about 4,000ft above the floor of the Colorado River valley

-The project was funded by David Jin, a Las Vegas developer, at a cost of $40 million (£20.5 million), and was built on the ancestral lands of the Hualapai Indian tribe

-Visitors will be charged $25 each to step out on to the walkway in special slippers

-The Grand Canyon itself runs 277 miles (446km) east to west, and ranges in width from a few hundred yards to 15 miles

-Contrary to popular belief, it is not the deepest gorge in the world — the Barranca del Cobre in northern Mexico and Hell’s Canyon in Idaho are deeper

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