Top 10 Cities for Urban Exploration

Aldwych station had a bustling side-life during World War II: This concert (with the audience standing on the tracks) was given by the Entertainments National Services Association in 1942. Topical Press Agency/Getty Images

Big draw: The London Underground

It's the oldest subway system in the world, with initial construction dating back to the 1850s, offering urban explorers something most underground railways can't: a seemingly unlimited supply of unused tracks, tunnels and stations.

There are long-vacant stations, including Down Street, which closed in the early '30s; and ones like Aldwych, closed to the public in the '90s (but still open to the occasional film crew), both of which sheltered Londoners during World War II bombing raids [source: Cooper].

Other underground paths, like the well-secured Post Office Railway line that closed in 2003, were in use so recently they offer a tour of lines in near-working condition for the most resourceful of urban explorers (read: those willing and able to commit the felony of breaking in) [source: Silent UK].

More to explore:

  • Millennium Mills: A flour mill built in the 1930s and one of the biggest ever in London, abandoned in 1992 and currently vacant [source: Derelict London].
  • Strand Union Workhouse: Built in the 18th century to house and employ the indigent, converted to an infirmary in the 1830s, when social services were cut back. Charles Dickens lived just blocks from the workhouse, and many believe it inspired "Oliver Twist" [source: BBC].

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