永定河
Chang'an Avenue starts from Dong Dan in the east and ends at Xi Dan in the west. Tiananmen and Tiananmen Square are located at the north and south of the center of the Avenue, respectively. The Avenue consists of two parts, West Chang'an Avenue and East Chang'an Avenue. The extension line extends east-west with Tiananmen Square as the center, extends westward to Shougang area, Yongding River and Western Hills, and extends eastward to Beijing City Sub-center, Grand Canal and Chaobai River. The core area of Chang'an Avenue and its extension is between Guomao Bridge of East Third Ring Road and Xinxing Bridge of West Third Ring Road (including Tiananmen area).