Pockets of Georgian architecture survived the war, but much of the city was levelled. There has been extensive redevelopment since <answer>World War II</answer>. Increasing traffic congestion in the 1920s led to partial demolition of medieval walls around the Bargate in 1932 and 1938. However a large portion of those walls remain.
Southampton has been redeveloped almost entirely in the years since which war?
World War II