An archaeologist works at the ancient Haifeng town ruins site in Huanghua, north China's Hebei Province, March 17, 2017. Chinese archaeologists began the second-stage excavation of the ruins here, expecting to unveil functions of the town as an important trade port during the Jin (1115-1234) and Yuan (1271-1368) dynasties in Chinese history. (Xinhua/Yang Shiyao)