Buckingham Palace was originally built as a town house for the Duke of Buckingham in the early 18th century
and was later bought by George III in 1761.
From 1820 John Nash was commissioned by George IV to build a new palace around the old house.
Nash constructed a three sided courtyard, open towards the Mall, with Marble Arch forming the entrace.
On the accession of William IV, Nash was replaced by Edward Blore who added a fourth side to the courtyard
and moved Marble Arch to its present day location.
Since 1837, during the reign of Queen Victoria, Buckingham Palace has served as the official London residence of Britain's sovereigns.