Tower cranes are a common fixture at any major construction site. They're pretty hard to miss -- they often rise hundreds of feet into the air, and can reach out just as far. The construction crew uses the tower crane to lift steel, concrete, large tools like acetylene torches and generators, and a wide variety of other building materials.

When you look at one of these cranes, what it can do seems nearly impossible: Why doesn't it tip over? How can such a long boom lift so much weight? How is it able to grow taller as the building grows taller? If you have ever wondered about how tower cranes work, then this article is for you. In this edition of HowStuffWorks, you'll find out the answers to all of these questions and more!

Thanks to Heede Southeast
I would like to thank Dennis Kenna and the crew at Heede Southeast for the real-world information and photos of the disassembly process that add so much to this article.

Heede Southeast, located in Charlotte, NC, supplies cranes for major building projects throughout the southeast. For info on renting cranes from Heede Southeast, call (704) 588-3985 or e-mail