If you are visiting London from outside of the United Kingdom, you will probably fly into one of the 3 major London airports which are Heathrow Airport, Gatwick Airport and Stansted Airport. The biggest of the airports is Heathrow which is one of the busiest airports in the world. Heathrow is 15 miles (24 kilometres) from the centre of London which can be reached easily by car and coach. There are numerous coach operators including National Express providing transport to London city centre from outside the terminal buildings. The rail link is provided by the Heathrow Express which is a station located at the airport that runs between Heathrow Airport and Paddington. Heathrow airport has 5 terminals and the Heathrow Express has 2 stops, Heathrow Central and Heathrow Terminal 5 which caters to passengers form all 5 terminals. Heathrow Airport is also served by the London Underground Picadilly Line which will connect you with the rest of the London Underground.
If you arrive at Gatwick, you will be 28 miles (45 kilometres) from the centre of London. Gatwick can also be easily reached easily by car and coach and once again there are numerous coach operators including National Express that will take you into the center of London. Gatwick like Heathrow also has its own train service called the Gatwick Express which will take you to London Victoria station
Stansted is 30 miles (48 kilometres) from the centre of London and has a train station beneath the terminal building. The train service connects you with Liverpool Street Railway Station in the centre of London which once again is also an Underground station allowing you to join the the Tube. London center is also easily accessible car and numerous coach operators including National Express.
If travelling from within the United Kingdom or from Europe by train, London is served by a number of major train stations including Waterloo, Paddington, King's Cross, St Pancras, Euston, Charing Cross, Victoria and London Bridge, most of which also double as Underground stations.
Once in London, there are plenty of opportunities for shopping and sightseeing. Sightseeing can be easily done by going on one of the many London bus tours that use the Routemaster. Not only are there the Routemasters used on the number 15 heritage route but there are many private companies utilising the old classic including 'National Trust Routemaster Tours', 'Red London Bus Tour', 'Hop-On Hop-Off Bus Tour', 'The Ghost Bus Tours' to name but a few.