to England throughout May, returning to Chicago in June. Filming took place in the lobby of One Illinois Center, which served as Wayne's penthouse apartment; bookcases were built to hide the elevators. A floor of Two Illinois Center was decorated for Wayne's fundraiser. The crew was described as excited as this scene depicted the first meeting between Batman and the Joker. The windows in both settings were covered in green screen material, allowing Gotham City visuals to be added later. In July, three weeks were spent filming the truck chase scene, mainly on Wacker Drive, a multi-level street that had to be closed overnight. During filming, Christopher added a set-piece of a SWAT van crashing through a concrete barricade. The sequence continued on LaSalle Street, which was also used for the GCPD funeral procession, for a practical truck-flip stunt and helicopter sequence. Additional segments were filmed on Monroe Street and Randolph Street, and at Randolph Street Station. Navy Pier, along the shore of Lake Michigan, served as Gotham Harbor in a climactic ferry scene. Scouts spent over a month searching for suitable vessels but were unsuccessful, so construction coordinator Joe Ondrejko and his team built ferry facades atop barges. The entire sequence was filmed in one day and involved 800 extras, who were moved through makeup and clothing departments in shifts. Exterior footage of the Gotham Prewitt Building, the site of Batman's and the Joker's final confrontation, was filmed at the in-construction Trump International Hotel and Tower. The owners refused permission to film a stunt in which Batman suspends a SWAT team from the building, so this was filmed from the fortieth floor of a separate building site. A former Brach's candy factory on Cicero Avenue scheduled for demolition was used to film the Gotham General Hospital explosion in August 2007. Filming in Chicago concluded on September 1, ending with scenes of Wayne driving and crashing his car, before the production returned to England. The Dark Knight includes Chicago locations such as Lake Michigan, which doubled as the Caribbean Sea where Wayne boards a seaplane; Richard J. Daley Center (Wayne Enterprises exteriors and a courtroom); The Berghoff restaurant (GCPD arresting mobsters); Twin Anchors restaurant; the Sound Bar; McCormick Place (Wayne Enterprises interiors); and Chicago Theatre. 330 North Wabash served as offices used by Dent, mayor Garcia, and commissioner Loeb; and its thirteenth floor appears as Wayne Enterprises' boardroom; Pfister enhanced