New York City is sometimes called the "City of Cities." It hasn't been a popular nickname, but it's been used increasingly as of late.

http://www.amazon.co.uk/exec/obidos/ASIN/6301687140/203-1149223-2167133
Video Visits - New York - City Of Cities

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John's Action Figure Column II 4/4/96 [LONG!]
... At which point I realized that absolutely *nothing* can be incongruous in this city of cities. ... (It must be a New York thing....) There *are* sales helpers ...
rec.toys.misc - Apr 5 1996, 2:55 pm by John Gersten

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New York = Macedonia
New York city, the incomparable, the brilliant star city of cities, the forty-ninth state, a law unto itself, the Cyclopean Paradox, the inferno with no-out-of ...
alt.news.macedonia - Feb 25 2003, 10:31 am by David Edenden - 1 message - 1 author

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GF and Cursim's crazy adventure in New York. (spot report)
The stage was set in the city of cities, the grandest place in America, New York City. After an unpleasant train ride during which ...
alt.roundtable - Sep 15 2003, 6:44 pm by Rich G. - 8 messages - 5 authors

24 June 1915, New York Times, pg. 10:
The New York of the future will truly be an imperial city of cities, worthy of the Empire State.

17 June 1926, Life, pg. 22:
"New York is the City of Cities, the Wonder Metropolis of the World. Whatever can be found elsewhere, that can be found elsewhere, that can be found also in New York." -- From a real estate circular.

3 May 2006, New York Sun, "Miss USA Arrives in the City of Cities" by Pranay Gupte, pg. 2:
"I'm a country girl with big-city dreams," Ms. Conner said. "And I've come to the city of cities."
(Tara Elizabeth Conner of Kentucky, Miss USA 2006 -- ed.)

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