Canal locks operate as massive, aquatic elevators that allow boats to essentially climb up and down hills by flooding enclosed chambers with thousands of gallons of water.

A closer look

Canal locks operate as massive, aquatic elevators that allow boats to essentially climb up and down hills by flooding enclosed chambers with thousands of gallons of water. When a vessel enters the lock, heavy watertight doors seal it inside, and water is either pumped in to raise the boat or drained out to lower it to the next water level, relying on nothing but gravity and ancient fluid dynamics. First invented in China over a thousand years ago, this deceptively simple engineering marvel is the only reason global shipping routes like the Panama Canal are physically possible today. Without these massive watery staircases, our entire global supply chain would instantly collapse, meaning the prompt delivery of your useless plastic trinkets from overseas relies entirely on some very large doors and basic plumbing principles