Walls of Xian China

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City Wall of Xian is an extension of the old Tang Dynasty structure, as a result of the wall-building campaign ordered by Zhu Yuanzhang, the first emperor of Ming Dynasty (from 1370 A.D.- 1375 A.D). After the enlargement, the city wall stands 12 meters (40 feet), 12-14 meters (40-46 feet) across the top, 15-18 meters (50-60 feet) thick at bottom and 13.7 kilometers (8.5 miles) in length with deep moats surrounding it. It boasts the most complete city wall to have survived through China's long history.