Some of the many secrets held by Buckingham Palace, including its former rat problem, and the part it played in Charles and Diana's courtship.

Part medieval fortress, part French chateau, Balmoral is not to everyone's taste but it provides a retreat from prying eyes for the royal family.

Built more than 900 years ago to house an army and a court, the actual work of building Windsor Castle was difficult because of the bubonic plague, which wipred out one-third of the population.

Sandringham in Norfolk, purchased in 1861 for Prince Edward, is one of the few royal residences owned personally by the Windsors.

The smallest royal residence currently in use, Highgrove House in Gloucester was renovated by Prince Charles and features a garden described as an "organic oasis."

Kensington Palace has been home to the extended royal family since the 17th century; Christopher Wren expands Nottingham House into a palace.