The gallery is at the west front of the Palace, on the site of a chapel bombed during the Second World War, and first opened in 1962. Over the following 37 years it received 5 million visitors, until it was closed in 1999–2002 for extension work carried out by John Simpson. On 21 May 2002, the gallery was reopened by Elizabeth II to coincide with her Golden Jubilee. The extension added the current Doric entrance portico and several new rooms, more than tripling the size of the building. It is open to the public for much of the year.