Nanjing City Wall, the largest ancient city wall in the world, was built in Ming Dynasty by the first Ming Emperor Zhu Yuanzhang from 1366 to 1386. It was listed as an important heritage site in 1988 by State Council of China. With an original length of 34 kilometers and a height from 14 to 21 meters, Nanjing City Wall is grand with a 14-meter foundation, 13616 crenels, 200 shacks and 13 city gates. Nowadays, a section about 19 kilometers was well- preserved for visiting.