Flak tower

Air defense towers used by Nazi Germany

Flak towers were large, above-ground, anti-aircraft gun blockhouse towers constructed by Nazi Germany. There were a total of 8 flak tower complexes in the cities of Berlin (three), Hamburg (two), and Vienna (three) from 1940 onwards. Other cities that used flak towers included Stuttgart and Frankfurt. Smaller single-purpose flak towers were built at key outlying German strongpoints, such as at Angers in France, and Heligoland in Germany.

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