Yantai is a prefecture-level city in northeastern Shandong province, People's Republic of China. Located on the southern coast of the Bohai Sea and the eastern coast of the Laizhou Bay, Yantai borders the cities of Qingdao and Weihai to the southwest and east respectively. The largest fishing seaport in Shandong and a robust economic center today, Yantai used to be known to the West as Chefoo, a misnomer which refers, in Chinese, solely to Zhifu Island, which is historically governed by Yantai. The contemporary name of Yantai came from the watchtowers constructed on Mount Qi in 1398, during the reign of the Hongwu Emperor, founding emperor of the Ming Dynasty. The towers served to raise alarms against invasions of Japanese pirates.