 These include a wall at a Liangzhu culture site, a stone wall at Sanxingdui, and several tamped earthen walls at the Longshan culture site.In 15th century BC the Shang dynasty constructed large walls around the site of Ao with dimensions of 20 meters in width at the base and enclosed an area of some squared.Walls of similar dimensions were also found at the ancient capital of the state of Zhao, Handan (founded in 386 BC), also with a width of 20 meters at the base, a height of 15 meters, and a length of along its two rectangular sides.