The 120 million square foot urban area will be built around a 2.4-mile long lake, and house up to 180, 000 inhabitants once complete.

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The City of Irvine, incorporated in 1971, is considered to be one of the largest planned urban communities in the nation, encompassing more than 65 square miles, some 200, 000 people, and featuring industrial zones, residential and recreational areas, and businesses.

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Mr. Zehetbauer separated from his wife in 2009 but was still living with her when he found the 6, 250-square-foot lot in an urban, increasingly gentrified neighborhood in the Northeast section of downtown Portland.

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But once one gets behind the relatively small urban core, the overall density is barely 2, 200 per square mile, less than half San Jose or Los Angeles, hardly a fifth that of Tokyo and not much more than Atlanta, the least dense major city in the world with more than 2.5 million residents.

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Julie Pham, a broker at Corcoran Group who has the Bond Street listing, said the views of old brick buildings and water towers from the 1, 500-square-foot terrace and the penthouse windows reflect the "urban alienation" in some of Moby's music and movie soundtracks.

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Urban areas in the UK cover around 16, 000 square kilometres.

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Expropriation brought into its hands about one-third of the urban space in the national-capital region (a rough square around Ottawa-Hull).

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Paul, Minnesota, Housing and Urban Development Secretary Donovan will meet with small business owners and area residents at the new Frogtown Square development.

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