The postcode is SW1A 1AA and it is one of the most famous addresses in the country, slap bang in the middle of Mayfair — one of the wealthiest areas of London. But the Queen resides there only on week days from February to March, May to July, and October to December. During that time she hosts state banquets, summer garden parties, investitures, diplomatic receptions and meetings. Prince Charles was born there, and the Queen, Charles, and William were all christened there. The palace has its own pool, where Kate taught Prince George to swim.