Clarence House.

Clarence House is a royal home in London, situated on The Mall, in the City of Westminster. It is attached to St. James's Palace and shares the palace's garden. For nearly 50 years, from 1953 to 2002, it was home to Queen Elizabeth, the Queen Mother, but is since then the official residence of The Prince of Wales, The Duchess of Cornwall and Prince Harry. Clarence House also served as the official residence for Prince William from 2003 until his 2011 marriage. It is open to visitors for approximately two months each summer.
The house was built between 1825 and 1827 to a design by John Nash. It was commissioned by Prince William, Duke of Clarence, who became King William IV in 1830. He lived there in preference to the nearby St. James's Palace, which he found too cramped. It passed to his sister Princess Augusta Sophia and, following her death in 1840, to Queen Victoria's mother, the Duchess of Kent. In 1866, it became the home of Queen Victoria's second son and fourth child Alfred, Duke of Saxe-Coburg and Gotha and Duke of Edinburgh until his death in 1900. His younger brother Prince Arthur, Duke of Connaught and Strathearn, Queen Victoria's third son, used the house from 1900 until his death in 1942, during which time the house suffered damage inflicted by enemy bombing. It was used by the Red Cross and the St. John Ambulance Brigade as their headquarters during the rest of World War II, before being given to Princess Elizabeth and her husband, The Duke of Edinburgh. Princess Anne was born there in 1950. After the death of George VI, the Queen Mother and Princess Margaret moved there in 1953, though the latter eventually moved to an apartment in Kensington Palace.
The house has four storeys, not including attics or basements, and is faced in pale stucco. It has undergone extensive remodelling and reconstruction over the years, most notably after the Second World War, such that relatively little remains of Nash's original structure. The Prince of Wales moved here in 2003 after the house underwent massive refurbishment following the death of his grandmother Queen Elizabeth, the Queen Mother. The house has been completely rewired, most of the major rooms were redecorated by the interior designer Robert Kime, and the building was given an external face-lift.
Since 2003 the term "Clarence House" has often been used as a metonym for the Prince of Wales' private office.