Location: Dien Hai Citadel is situated in Thach Thang Ward, Hai Chau District,Da Nang.

Characteristics: The Dien Hai Citadel, built in 1813 in the twelfth year of Gia Long’s reign by Da Nang’s estuary, used to be considered as Dien Hai Fortress.

In the fifteenth year of Minh Mang’s reign, after being moved inland and rebuilt in brick on a high mount in 1823, in the fourth year of Minh Mang’s reign, The Dien Hai Citadel was given another name in 1835. In 1840, after looking over the Defenses of Da Nang, Deputy Minister of Labor Nguyen Cong Tru requested a stronger system for Dien Hai and An Hai Citadels.