Out on the edge of The Ledge

CHICAGO -- On a clear day, you can see 50 miles in all directions from the tallest building in the Western Hemisphere, but the view that has people flocking to this 108-story edifice is barely a quarter-mile away.

It's a quarter mile straight down -- a sheer, breath-catching 1,353-foot plunge to South Wacker Drive and the Chicago River below.

The Ledge -- or perhaps more properly the ledges because there are four of them -- is an innovative addition recently installed on the west-facing wall of the Skydeck, the observation platform on the 103rd floor of the Willis Tower, the structure previously known as the Sears Tower.

The Skydeck has been drawing crowds since it opened in 1974, last year enticing 1.3 million visitors to take the one-minute elevator ride up to enjoy the incomparable view.

But as a way of keeping the image of this Chicago icon burnished and its operating systems on the cutting edge, the owners on June 24 announced plans for an array of innovative measures intended to slash the building's base energy consumption by 80 percent, its water usage by 40 percent and to explore options to take advantage of its height to generate electricity with Windy City wind. These improvements are to be phased in over five years.

To keep tourists coming, they also opened the Ledge on July 2 to immediate acclaim.

Intended to give Skydeck visitors unusual vantage points, each of the four ceiling-high glass boxes measures 8 feet wide and extends 4.3 feet out from the building's western wall, which although not the direction with the most dramatic view, is the only side that offers a straight drop to the ground. Designed so they can be drawn in for window cleaning and maintenance, the units are suspended from above and the three-layer panels of half-inch glass discreetly clipped together, creating a support system that, though nearly invisible, will support five tons of thrilled spectators.

Judging by the steady throng of people who congregated along the ledges on the August afternoon I visited, they have a hit on their hands. Don’t be surprised if the Skydeck is added to more travel lists of the top things to do in Chicago when visiting.

While small groups of visitors milled along the three sides of the Skydeck that offered more dramatic vistas of Lake Michigan, Millennium Park and Chicago's glittering thicket of skyscraping architecture, they stood in lines three and four deep at the ledges. Their anticipation and anxieties were visible while they waited to step over the edge of the ledge. Once on the clear platforms, they quickly clicked a picture of their friends or kids posing against the glass, the people in the adjacent bay, or their own feet framed by the emptiness below.

"Look, ma, we're flying!"