Final answer:
The Berlin Wall, erected in Berlin by East Germany in 1961, served as a symbol of the Cold War and divided the city into two parts.
Step-by-step explanation:
The German city in which a giant wall was put up as a symbol of the Cold War is Berlin. The Berlin Wall, erected by East Germany in 1961, divided the capital of Berlin into two parts, and it served as a physical barrier between East and West Germany.