Heathrow has a tube (London Underground) station - with a line in to central London, you will have to change at Piccadilly Circus to the Bakerloo line, and change at
Marylebone to the British Rail
service to Aylesbury (Chiltern Line)
Arrives at Waterloo station in London, transfer to the Bakerloo line (London Underground) and take the tube to Marylebone, change to the British Rail service (Chiltern Line) to Aylesbury
