The massive Three Gorges Dam in China calls for some creative engineering.
The Three Gorges Dam in China's Hubei province presents quite an engineering challenge. A 600-foot one, to be exact. Engineers' ingenious (if a little insane) solution to transporting boats over the dam was to build the world's largest elevator. It's actually a bit more like a giant mobile swimming pool—the boats float into the watery elevator and remain in the water for the duration of the lift before sailing out on the other side, several hundred feet later.
The elevator itself weighs 15,500 tons, and can carry ships up to 370 feet. The elevator takes 40 minutes to do its magic, reducing the time needed to get around the dam dramatically (ships used to use a long detour). This means the shipping capacity of the dam will increase by six million tons of goods a year, an increase which explains why anyone would build an epic contraption like this in the first place.