Number 10 Downing Street has been the official residence of the British Prime Minister since 1732. It contains a Cabinet Room in which government policy is decided, an impressive State Dining Room and a private apartment; outside is a well-protected garden.

The building is much larger than it appears from its frontage. The hall with the chequered floor immediately behind the front door lets on to a warren of rooms and staircases. The house in Downing Street was joined to a more spacious and elegant building behind it in the early 18th century. Number 10 has also spread itself out to the left of the front door, and has taken over much of 12 Downing Street, which is accessed by a corridor that runs through 11 Downing Street – the official residence of the Chancellor of the Exchequer.