The Chinese have called it their ââ¬ÅUnderground Great Wallââ¬Â ââ¬â a vast network of tunnels designed to hide their countryââ¬â¢s increasingly sophisticated missile and nuclear arsenal.
For the past three years, a small band of obsessively dedicated students at Georgetown University has called it something else: homework.
http://news.yahoo.com/digging-china-nuclear-tunnels-013008319.html

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