"First House on the Square". After further demolition the new Zeil, Schillerstrasse and Goethestrasse were laid. The extension of the Neue Mainzer Straße was finished in 1874 with a bridge named Untermainbrücke. The newly built home of the stock exchange was opened in 1879 close to Hauptwache. The opera house was established and inaugurated in 1880 following the donations of Frankfurt's citizens. The new law courts were opened in Heiligkreuzstrasse in 1889 and followed by the theatre in Untermainanlage in 1902. The rapid process of growth in the new city led to the formation of a town centre. The previous residential districts developed into a commercial and business centre and the residents were soon ejected from the area. The trams were changed to electrical operation from 1899, whereby the city had a modern and efficient traffic service. The central traffic node of the trams was situated at Hauptwache, numerous lines lead through the Zeil, which developed into a road of large department stores. In the years after the first world war the emphasis of the development concerning town construction shifted more towards the outside quarters. The medieval parts of the city centre fell victim, as those in the Gothic Altstadt did, to the numerous allied air raids of 1943-44. Above all the reconstruction considered the needs of urban traffic and accepted modern town planning. Thus, completely new traffic axles were laid, for instance, Konrad-Adenauer-Strasse and the Zeil were considerably widened during their reconstruction. The redevelopment of the city centre brought the Innenstadt into the 1960s. The building of the underground system changed and from 1963, after intense construction measures, a large underground rapid-transit station was built underneath Hauptwache and Konstablerwache. The Zeil and the Freßgas were turned into pedestrian zones and until 1986 most tram lines were shut down. In the western part of the Innenstadt a banking quarter formed around the model of the American Central Business Districts. Since the 1970s this western part has seen numerous new skyscrapers, the best known of which include the Eurotower at Willy-Brandt-Platz and the Commerzbank Tower at Kaiserplatz. Economy All Nippon Airways and Japan Airlines have their Frankfurt offices in Innenstadt. References External links Frankfurt Innenstadt at City of Frankfurt Districts of Frankfurt Frankfurt am Main