Buckingham Palace is the London residence and administrative headquarters of the British monarch. It was originally constructed in 1703 as a large townhouse but became the palace in the 19th century. The palace contains over 775 rooms across 39 acres, including 19 state rooms, 52 royal bedrooms, and the largest ballroom in the palace. While the Queen's primary residence is Windsor Castle, Buckingham Palace still serves as the administrative center for the monarchy and welcomes over 50,000 guests each year for events.