London Underground

The London Underground (or simply the Underground or the Tube) covers a good portion of London, but there were constant line and station closures (both announced and unannounced).

Oyster cards are used for ticketing. Fees are based on zones you travel between. Calculating fees can be confusing for out-of-towners, or you can just load up the Osyter card and not worry about it.

Oyster card

the Underground entrace

the Underground during rush hour