Pan Gate. Suzhou, China.

"Pan Gate, was first built during the Wu Kingdom of Spring and Autumn Period (770BC-476BC) and it is the only well preserved water-and-land city gate in the world now. It consists of the land city gate, the water city gate, the city gate tower, the barbican and the city wall on both sides. It was a place with utmost importance for the army in ancient times," Travel China Guide.