Throughout the history of architecture, there has been a continual quest for height. Thousands of workers toiled on the pyramids of ancient Egypt, the cathedrals of Europe and countless other towers, all striving to create something awe-inspiring. People build skyscrapers primarily because they are convenient -- you can create a lot of real estate out of a relatively small ground area. But ego and grandeur do sometimes play a significant role in the scope of the construction, just as it did in earlier civilizations.

Photo courtesy Wayne Lorentz: Glass, Steel & Stone
The two towers in New York's World Trade Center stood 1,360-feet (415-meters) tall, with a massive steel truss at their core.

Up until relatively recently, we could only go so high. After a certain point, it just wasn't feasible to keep building up. In the late 1800s, new technology redefined these limits. Suddenly, it was possible to live and work in colossal towers, hundreds of feet above the ground.

In this article, we'll look at the innovations that made these incredible structures possible. We'll examine the main architectural issues involved in keeping skyscrapers up, as well as the design issues involved in making them practical. Finally, we'll peer into the future of skyscrapers to find out how high we might go.

The Twin Towers
When the twin towers of the World Trade Center were struck on September 11, 2001, it seemed at first that they might remain standing. But in less than two hours, both towers had collapsed to the ground. Click here to find out how the remarkable structural support system in these buildings eventually gave way.