Downtown Shanghai is bisected by the Huangpu River, a man-made tributary of the Yangtze created by order of Lord Chunshen during the Warring States period. The historic center of the city was located on the west bank of the Huangpu (Puxi), near the mouth of Suzhou Creek, connecting it with Lake Tai and the Grand Canal. The central financial district, Lujiazui, has been established on the east bank of the Huangpu (Pudong). Along Shanghai's eastern shore, the destruction of local wetlands due to the construction of Pudong International Airport has been partially offset by the protection and expansion of a nearby shoal, Jiuduansha, as a nature preserve.