August 9, 2008:  China has recently completed major upgrades to a complex of naval bases at Zhoushan and Dinghai (about 180 kilometers south of Shanghai). Over a dozen submarines and over 30 destroyers and frigates can operate of this complex, most of them in underground docks dug into seaside hills. There are also repair and maintenance facilities, as well as underground fuel and ammunition depots. Nearby air bases for naval aviation also feature some underground hangers, and many above ground aircraft shelters.

This complex of bases was built up since the 1990s, in anticipation of an invasion of Taiwan. While China has backed off on the aggressive rhetoric of late, building continues at these naval bases.