From: HowStuffWorks on Fri, Dec 18 2009 2:06 AM

From: HowStuffWorks on Fri, Dec 18 2009 2:05 AM

From: HowStuffWorks on Tue, Sep 29 2009 5:02 PM

One of the biggest concerns of the Big Dig was how to bury I-93 under the current subway stations. Watch how engineers develop a solution on "Extreme Engineering" on Discovery Channel.

From: HowStuffWorks on Tue, Sep 29 2009 5:01 PM

Meet the ambitious development team for the Turning Torso apartment building in this clip from "Extreme Engineering" on Discovery Channel.

From: HowStuffWorks on Tue, Sep 29 2009 5:00 PM

As the Boston tunnel sections neared completion, engineers were preparing to launch them. The question was, would they float? Learn more in this clip from "Extreme Engineering" on Discovery Channel.