Potsdamer Platz-formerly Europe's busiest square until WWII, the area was occupied by the Wall and death strip until reunification. Now, it is entirely privately owned by Daimler-Chrysler (Mercedes) and Sony, who stepped in as big investors to rebuild the former 'no-man's land.' The buildings were designed by Arata Isozaki, Helmut Jahn, Renzo Piano, and Rafael Moneo. Helmut has done several buildings in Chicago, including the massive State of Illinois structure, which this winged dome reminded me of, and the coloring of the square below