 GEOG: Leicester Square, Piccadilly Circus, Green Park, Hyde Park  Corner (not "Hyde Park"), Acton Town, Hounslow East, and Hatton  Cross stations occur in that order along the Piccadilly Line. The  other 12 stations in between, at which all trains stop, should also  have been mentioned. Marble Arch and Oxford Circus are on the  Central Line, not the Piccadilly, while Hampstead Heath is not on  the Underground at all, but was a British Rail station.