Sidu River Bridge, China

Connecting Shanghai to Chongqing, the Sidu River Bridge in China is quite a colossal structure. Built in 2009, the 1,222-mile long bridge was China’s most expensive overpass at $100 million. And it was also the most difficult to build considering the surrounding terrain and the fact that it sits 1627 feet above the lowest portion of the ground below. Surely, just by looking at this photo, one can already feel their stomach flip at the idea of looking all the way down to the valley below.