Dagukou Emplacement is located in Dagukou at the confluence of the Haihe River and the Bohai Sea in Tanggu District. It is the ancient sea gateway to Beijing and Tianjin,  with an important strategic significance in ocean defense. 
    Dagukou Emplacement was originally set up in the later Ming Dynasty.  Five large emplacement were constructed in 1858, the eighth year of Emperor Xianfeng's reign, and three of them were seated on the southern bank and the other two were on the north. They were named “Wei”, “Zhen”, “Hai”, “Men”, and “Gao” respectively, with 25 small emplacements as attachments. Most of them were dismantled when the Eight-Power Allied Forces invaded China in 1900.  Today,  there are only three Emplacements still remained,  which are named as “Wei”, “Zhen”, “Hai”. 
    Dagukou Emplacement was listed as an important historical site in 1988,  and was opened to the public in June 1997.  It is an important witness of modern China's fight against invasion.