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NICKNAMES OF PLACES AND THINGS

Initial caps, roman, no quotation marks if well established:
            Philadelphia or Philly
            Los Angeles or L.A.
            Beirut, Paris of the Middle East
            Chicago, often called the Windy City
            Kansas, the Sunflower State
            the Old Lady of Threadneedle Street (the Bank of England)
            Old Bailey (criminal court of London)
            Mighty Mo (battleship Missouri)
            Fighting Lady (carrier Lexington)
            Flying Tigers

If not well established, use quotation marks and lowercase:
            Upper Marlboro, self-styled "tobacco capital of Maryland"
            Christchurch is known as "the most English city outside England"
            itself called the "Cinderella of the rust belt"

For shortened proper names not commonly used, initial cap and quotation marks are used:
            Kwajalein or "Kwaj"