Spudgun67 on Wikimedia Commons Heritage Architecture The Gutzlaff Signal Tower. Built in 1907 Reinforced concrete structure. Waitan, Huangpu, Shanghai 15 Feb 1994 by Shanghai Municipal Government on 15 February 1994 Colour: stone Wikimedia: Flickr: How to add yours Spudgun67 on Wikimedia Commons Spudgun67 on Wikimedia Commons Google Streetview OpenStreetMap