The Queen's Gallery at Buckingham Palace has reopened after a £20m redevelopment and expansion.

John Simpson and Partners was appointed architect in 1998 after a limited competition, and given the brief of creating a gallery with 'presence and identity' and a 'bold new entrance'.

The project was paid for entirely by the Royal Collection, through public admissions to the Queen's official residences - Buckingham Palace, Windsor Castle and the Palace of Holyroodhouse - and retail activities.

Simpson has created three and a half times as much display space as the old gallery offered, with seven exhibition rooms.

The gallery currently has a collection of 450 works from nine royal residences and includes painting, sculptures, jewellery and manuscripts.

The original gallery was opened in 1962, within a building completed in 1831 but which was destroyed in an air raid in 1940s and subsequently redeveloped to house the Queen's Gallery. It now forms one section of the new Queen's Gallery called the Nash Gallery - named after its 19th century designer. Details: www.royal.gov.uk