A spectacular roadway some 120 miles long, the Overseas Highway links mainland Florida with the Florida Keys, and contains 51 bridges, including the Seven-Mile Bridge. Explore its history and design.

New Orleans' Lake Pontchartrain Causeway is an engineering marvel: Two ribbons of concrete-at nearly 23.87 and 23.88 miles long each-form the world's longest automobile bridge.

This is the story of the Columbia, the first shuttle to fly to outer space, from inception to tragic demise in January 2003.