The idea was to drain the Mediterranean by building several huge dams, the principal ones being across the straits of Gibraltar and the Bosporus.
By sealing off the inflow of water, the sea could be gradually lowered by more than 200 meters, opening up land routes from Morocco to Spain and from Tunis to Italy and increasing vast swaths of arable land.
With easy travel between Europe and Africa, a supercontinent would emerge to challenge the rival powers of Pan-Asia and Pan-America. The dams would provide unlimited hydroelectric power.
Unfortunately for Sörgel, the Nazis had no interest in the scheme, though the idea stayed alive for a few more decades. In 1977, Popular Mechanics analyzed the engineering challenges and concluded:
"It would require a dam 18 miles long and up to 1,000 feet deep and 1,500 feet wide at its base. The volcanic Mediterranean seafloor, relieved of all that weight, might react in eruptions and earthquakes, and the sea level everywhere else in the world would rise by three feet."Atlantropa in The Futility Closet
Atlantropa on Wikipedia
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