Defense Structures

One of the most impressive military defence works in the history of humanity is the Great Wall of China, 6,350 kilometres in length. The last volume in the series is dedicated to an exhaustive study of the history and building techniques of the Great Wall. Together with the nine fortified border towns it served to defend every inch of the massive land from invasion. Other fortified cities are also included with their watch-towers, moats, city walls and city gates: Changan (Xian), Luonyang, Jianye (Nanjing), Kaifeng und Beijing.