Chicago - The Sears Tower

For many years the world's tallest skyscraper, the Sears Tower is really nine buildings combined into one massive structure. Completed in 1974, it was erected to consolidate offices housing 6,500 Sears employees from all over the city.

Close to the famed Chicago 'L', the elevated train and Chicago Transit Authority buses, it would have been taller but the Federal Aviation Authority was concerned about plane safety on routes to and from O'Hare.

The buildings are comprised of a set of 'bundled tubes' in which each tower supports others. Owing to the strong winds in Chicago, produced by its proximity to Lake Michigan, any tall building has to take careful account of stresses produced by wind shear. With its special design, the perimeter can shed winds and reduce sway, while the interior provides structural support.

A series of setbacks above the 50th floor give the structure its unique look, along with the black glass that provides both light and temperature control and an impressive facade. As a result, it forms a significant addition to an already magnificent skyline in one of America's premier cities.

Visitors can take the elevator to the Skydeck to see the view at the 103rd floor. The entrance is on Jackson Boulevard and 1.5 million visitors pass through it every year.

First step on the tour after you get your tickets is a video that explains the history and unique construction of the building, very interesting all on its own. Then it's on to the SkyDeck elevators where you are whisked to the top. Elevators are equipped with 50-inch flat screen monitors with views of the Earth from the Space Shuttle, compliments of NASA.

On a clear day visitors can see for dozens of miles and, thanks to the high winds, the sky is often clear. The view is entangled by other structures nearby, but you'll see not only the other buildings but parts of Michigan, Indiana and Wisconsin stretching into the distance.

There are interactive computer displays that give you tons of information about the history of Chicago and its world famous buildings. Cut-out windows allow the kids to see as well as the adults. High-powered telescopes provide for a closer look at some of the other sights of the city.

The Tower also offers several restaurants to choose from including Mrs. Levy's Delicatessen, a New York style deli, Mia Torre for Italian cuisine and Dos Hermanos offering a Mexican menu.

The surrounding space at the base of the tower is somewhat plain, but the view looking up is spectacular. In order to relieve the blandness of the plaza, a 4-story atrium was erected on Wacker Drive that is worth a look.

Lines can be very long and there are often long waits not only for tickets but elevators in both directions. Be sure to allow plenty of time to get to the top or bottom. Aim for a Sunday morning or other low-traffic time.