Production designer John Vallone and his team constructed an elevated train line on the backlot of Universal Studios that perfectly matched the ones in Chicago. The film crew tarped-in the New Street and Brownstone street sets to double for the Richmond District setting, completely covering them so that night scenes could be filmed during the day. This tarp measured 1,240 feet long by 220 feet wide over both sets, and cost $1.2 million to construct. However, this presented unusual problems. The sound of the tarp flapping in the wind interfered with the actors’ dialogue. Birds who had nested in the tarp provided their own noisy interruptions.