Why do u think Berlin was divided into four zones even though the city was located in the middle of the Soviet zone of Germany

After its unconditional surrender, Germany was divided into four zones of Allied military occupation: American, French, British, and Soviet. The old capital of Berlin was also divided into four zones, but Berlin itself remained inside of the Soviet zone.

Berlin was devised into four zones because while most of the allies had most of Germany there was a small piece own by the soviets and in Berlin it was split into east and West Berlin one being democratic and one being communist