http://news.bbc.co.uk/1/hi/sci/tech/6897293.stm Tests begin on Canaries telescope] BBC 14 July 2007 Giant telescope begins scouring space 14 July 2007 With a primary mirror of 10 meters , it is currently the world's largest optical telescope, located at the Roque de los Muchachos Observatory on the island of La Palma, in the Canary Islands in Spain.