Oderturm

Der Oderturm is a 24-storey, 95 m office skyscraper in Frankfurt, Germany, built between 1968 and 1976 when the city was part of East Germany. It is arguably the tallest office building in Brandenburg, with a mobile telephony mast. Its 89 m roof is 1 m less than that of the Stern-Plaza in Potsdam, built in 1998. The 107 m hall containing Tropical Islands and the 161 m steam generator at Schwarze Pumpe power station are taller structures, though they lack occupied floors.

Source: Wikipedia