De Lattre Line
The De Lattre Line, named after General Jean de Lattre de Tassigny, was a line of concrete fortifications, obstacles, and weapons installations constructed by the French around the Red River Delta in northern Vietnam. The French established the fortification to guard the essential lines of communication between the cities of Hanoi and Haiphong and to provide security for the densely populated and economically important Delta area against attacks by both the Việt Minh and any potential invasion from Communist China.