How long is the longest single residential building in the world?

Karl-Marx-Hof was built between 1927 and 1930 by city planner Karl Ehn, a follower of Otto Wagner. It held 1,382 apartments. Only 18.5% of the 156,000 m²-large area was built up, with the rest of the area developed into play areas and gardens. At over a kilometre in length (1,100 metres)) and spanning four Straßenbahn (tram) stops, Karl-Marx-Hof is the longest single residential building in the world.