Many United States Army installations are known as forts, although they are not always fortified. During the pioneering era … See more

From very early history to modern times, walls have been a necessity for many cities. Amnya Fort in western Siberia has been described by archaeologists as the oldest known fort. In Bulgaria, near the town of Provadia a … See more

Forts in modern American usage often refer to space set aside by governments for a permanent military facility; these often do not have any actual fortifications, and can have specializations (military barracks, administrati… See more

Fortifications designed to keep the inhabitants of a facility in rather than attacker out can also be found, in prisons, concentration camps, and other such facilities. Those are covered in other articles, as … See more

• Border barrier
• Defense line
• Imperial fortress
• List of fortifications
• List of forts… See more

• July, Robert Pre-Colonial Africa, Charles Scribner, 1975.
• Murray, Nicholas. "The Development of Fortifications", The Encyclopedia of War, Gordon Martel (ed.). WileyBlackwell, 2011.… See more