Windmills vs. water
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The windmills of Kinderdijk started spinning in 1738 to help make this whole patch of Dutch farmland possible. Each of the 19 windmills is equipped with a huge Archimedes' screw able to channel vast volumes of water upwards, making dry (well, maybe a little soggy) land out of what was once a six-foot-deep salt swamp. Water is pumped over a massive ring of dikes into tidal rivers that carry discharge to the sea, keeping this large, below-sea-level basin—known as a polder—from flooding. The work is done by modern pumping equipment nowadays, but Kinderdijk's giants could yet awaken: The great windmills are kept fully functional as backups.