Introduction to Dongshuiguan: Dongshuiguan is a cultural relic protection unit in Nanjing with a history of more than 1,000 years. It is located outside Tongji Gate and on the west side of Longpan Middle Road. It is a water pass where the Qinhuai River flows into Nanjing City. Dongshuiguan integrates Shuiguan architecture and city wall architecture, which is rare in the history of national architecture and can be regarded as a unique one.