The project started in 1937. A huge model was made, and entire parts of the city of Berlin were removed, at the same time as the Holocaust was planned. Hitler wanted to call Hitler's "Nazi dystopia" "Welthauptstadt Germania" and, in theory, was supposed to be ready in 1950.
Schaper already impressed Hitler with his work in Nuremberg, where he deliberately reinterpreted classical architecture in massive and many Nazi buildings designed to frighten and increase power.
The idea of Sper and Hitler was to take all the monumental buildings, boulevards or sculptures that Europe has and make copies, only a few times larger. Most of those beauties would be the seven-kilometer long boulevard that best illustrated the size and power of Nazi Germany.
In the south there would be a triumphal gate, like the one in Paris, only six times larger. To the north, the boulevard would open to the ice for holding parades.
https://www.youtube.com/watch?time_continue=960&v=dOXmrVR00RI