From the dawn of history to the present, men have labored unceasingly to surround their homes with impregnable fortifications while at the same time they have tried to discover more powerful weapons to smash through the defenses of other men. The Romans and the Chinese had their great walls; the feudal lords of the Middle Ages had their moated castles; and to modern times belong the Maginot and the Siegfried Lines and the atom bombs. In these great efforts, and countless others like them, man has confidently sought permanent security. But no man or nation has yet devised a refuge safe against new weapons and new tactics of a determined enemy. The age-old struggle between offense and defense is the principal story of Fort Pulaski.