Hitler wanted to turn Moscow into a huge artificial lake. As the German armies were approaching the Soviet capital in the Operation Typhoon in the autumn of 1941, Hitler determined that Moscow, like Leningrad and Kiev, would be levelled and its 4 million inhabitants killed, to destroy it as a potential center of Bolshevist resistance. For this purpose Moscow was to be covered by a large artificial lake which would permanently submerge it, by opening the sluices of the Moscow-Volga Canal.
