Royal Mail and the London Underground

In 2013, the London Underground turned 150 years old! Royal Mail swooped in and created stamps to commemorate this huge milestone in London transport. They show specific scenes from throughout the Tube's history, from 1863, with the opening of the Metropolitan Line all the way to 1999, with the opening of Canary Wharf on the Jubilee. In order, the events are:

1863: The Metropolitan Line opens
          Stamp shows a steam train approaching Paddington.

1898: Tunneling under London streets
          Stamp shows construction workers working a boring machine under a street.

1911: Commute to the suburbs
          Stamp shows Edwardian folk commuting in and out of Central London.

1934: Art Deco on the Piccadilly
          Stamp shows Boston Manor station, constructed along with many others in the 20s and 30s in the art deco style.

1938: Classic Rolling Stock
          Stamp shows the classic tube trains, back then a London icon.

1999: Jubilee line at Canary Wharf
          Stamp shows Canary Wharf station, one of the most modern on the whole network and DLR.
Shown: First Day Cover

Along with these, they also made a poster mini set, featuring famous tube advertisements and, well...posters.

Shown: First Day Cover

Released January 9, 1863 in London W2 postcode.

Otherwise, in 2009, a tube map stamp was released in the British Design Classics set, along with things like the Concorde, Routemaster, and Mini.

Released January 13, 2009, in Birmingham Longview post office with the British Design Classics set.