The Black Door, by the Norwegian artist Svein Moxvold, was created for his degree show at Goldsmiths, University of London in 2005. He donated it to Goldsmiths when he left, and it still stands on the site where it was originally displayed on College Green.
Mr Moxvold worked in typography and advertising until he was in his fifties, when he decided to pursue his youthful dream of becoming an artist. After a two-year foundation course in his native Norway, he studied for a BA in fine art at Goldsmiths from 2002 to 2005.
Shortly after his arrival in London, he took part in the huge march protesting against the war in Iraq. The Black Door reflects his political concerns and is intended to evoke the door of 10 Downing Street, which is also made of black steel and has the same knocker design.
The door was built in the college's metal workshop.
Mr Moxvold said he was always delighted when "children and students left their mark by hanging their training gear on it or using it for football practice".
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