In Cappadocia, Turkey, a man knocked down a wall of his home and discovered a huge underground city.

在土耳其的卡帕多西亚，一名男子推倒了他家的一堵墙，发现了一座巨大的地下城市。

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The Underground City: June 1934

图4 地下城市：1934年6月

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Many people believe building an underground city is one way to alleviate the problem.

许多人认为，建造地下城市是减缓该问题严重性的一种方法。

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His idea started when he heard two religious workers playing music for free in New York City's underground transportation system.

VOA: special.2009.07.31

So far this month, U.S.officials have sent around to other Mexican border cities with the hope that many of them will not work their way back to Juarez and become part of the city's criminal underground.

VOA: standard.2010.04.01

But we're not going to wait forever,". Kelly said preparations have been made for a visit Sunday by IAEA inspectors to the partially-underground enrichment facility near the city of Qom that Iran recently acknowledged it has been secretly building.

VOA: standard.2009.10.24

Considering its age, the underground city is in excellent condition and is accessible today via numerous tours.

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The hotel sits directly above the Bonaventure metro station and underground city, making it popular with conference groups.

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And it's not a short drive in what is in effect an underground city.

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