Ancient Wisdom: Making the City Wall Strong as Iron
Songpan Wall was a city wall built on a mountain in northwestern Sichuan Province, China. At an altitude of just over one mile high, it is 3.85 miles in length, 41 feet in height, and more than 40 feet wide. Each massive brick weighs 66.1 pounds. It was embossed with elegant designs. The length, height, ...
