Huangya Water Pass

　　   Huangya Water Pass is a well-known water gateway along the Great Wall in eastern Beijing. It controls the Gou River valley, linking Taipingzhai to the east and Huangyaguan Fort to the west. Construction began during the Yongle period (1403–1424) of the Ming Dynasty. The upper part features crenellated battlements and a parapet walkway, while the lower section has five arched water passages. The entire structure spans 75.5 meters in length and reaches a total height of 12.15 meters. The crenellations were equipped with iron cannons and bronze guns, and the five water arches were fitted with barrier gates and sluices. During wartime, it served to repel enemy forces, while in peacetime, it functioned as a customs checkpoint for taxing goods. Due to years of neglect and deterioration, the wall collapsed, but in 1992, the Tianjin Municipal Government restored it on the original site. A temporary bridge was also built over a gap in the nearby Jinwei Highway to connect it with the northeast corner tower of the fort.