In 1987, Japan began building an airport where there had never been land before—right in the middle of the sea, twenty meters above the muddy bottom. Three mountains were razed to create the island. It later turned out that the engineers had miscalculated, and the island began to sink faster than expected—by half a meter per year.

This video tells the story of Kansai Airport: how the most expensive project in human history was built, how an earthquake and a devastating typhoon tested its strength, and why thousands of hydraulic jacks still keep the terminal afloat every year, millimeter by millimeter.

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