Dahan Stronghold was constructed in 1975 with the aim of controlling the Meishi'ao and Juguang sea lanes. Located on a promontory between Tieban Beach and Beihai Tunnel, the fortification comprises three layers of tunnels. The uppermost layer of tunnel is 304m long, 1.5m wide, and 2m high. Inside, anti-aircraft gun batteries, a munitions store, and soldiers' dormitories are among the facilities that make this impressive site a mustsee for any true military enthusiast.After the army left, Dahan Stronghold was taken over by the Matsu National Scenic Area Administration, which completed renovation of the site in 2006. The structure was opened to the public on February 10, 2007.