Green Templeton College (GTC) is a constituent college of the University of Oxford in the United Kingdom. It is the university's newest college having come into existence on 1 October 2008 from the merger of Green College and Templeton College. The college is located on the previous Green College site on Woodstock Road in North Oxford and is centred around the architecturally splendid Radcliffe Observatory, an 18th century building, which is modelled after the ancient Tower of the Winds in Athens.