former home of the family of composer Felix Mendelssohn (1809–47) in Leipziger Strasse before moving in 1894 to the vast new edifice near the Brandenburg Gate, erected by Paul Wallot (1841–1912). Next door, the Herrenhaus, or Prussian House of Lords (the Upper House of the Prussian State Parliament), occupied a former porcelain factory for a while, before moving to an impressive new building erected on the site of the former Mendelssohn family home in 1899–1904 by Friedrich Schulze Colditz (1843–1912). This building backed on to an equally grand edifice in the next street (Prinz-Albrecht-Straße), also by Colditz, that had been built for the Preußischer Landtag (the Prussian Lower House), in 1892–9. Potsdamer Platz was also the location of Germany's first electric street lights, installed in 1882 by the electrical giant Siemens, founded and based in the city. Interwar years The heyday of Potsdamer Platz was in the 1920s and 1930s. By this time it had developed into the busiest traffic center in all of Europe, and the heart of Berlin's nightlife. It had acquired an iconic status, on a par with Piccadilly Circus in London or Times Square in New York. It was a key location that helped to symbolize Berlin; it was known worldwide, and a legend grew up around it. It represented the geographical center of the city, the meeting place of five of its busiest streets in a star-shaped intersection deemed the transport hub of the entire continent. These were: Königgrätzer Strasse (northern portion), earlier names Brandenburgische Communication and then Schulgartenstrasse, running along the former route of the customs wall and leading north to the Brandenburg Gate. After a brief spell as Budapester Strasse in the late 1920s (although this name was not widely recognised), on 6 February 1930 it was renamed Ebertstrasse after Friedrich Ebert (1871–1925), first President of Weimar Germany. In 1935 the Nazis renamed it Hermann-Göring-Strasse after Reichsmarshal Hermann Göring, whose official residence was on the east side of the street near the Brandenburg Gate. On 31 July 1947, it reverted to Ebertstrasse. Königgrätzer Strasse (southern portion), earlier names Potsdamer Communication and then Hirschelstrasse, also running along part of the customs wall's old route, actually leading mainly south east. On 6 February 1930, it was renamed Stresemannstrasse after Gustav Stresemann (1878–1929), the first Chancellor to serve under President Ebert. In 1935 the Nazis renamed it Saarlandstrasse after the region of southwestern Germany that had