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Castles: The Ultimate Defense Fortress

It Turns Out Kings and Preppers Have a Lot in Common

This stone castle, the Bedzin Castle in Silesian, Poland dates back to the 14th century.

This stone castle, the Bedzin Castle in Silesian, Poland dates back to the 14th century. (View larger version)

By Patrick J. Kiger


Today, tourists who visit Great Britain’s Dover Castle, the sprawling, picturesque 80-acre complex, may seem like a backdrop for a fairy tale. But when royal architect Maurice the Engineer built the castle in the late 1100s, all that massive stonework wasn’t just meant to impress visitors with its grandeur.

In Medieval times, castles were the backbones of royal power, the means by which Maurice’s employer, Henry II, would maintain control of the countryside and defended it from invaders if necessary. Henry, himself a feared warrior, knew a few things about overwhelming opponents’ fortifications, and it’s likely that some of his insights made their way into the design of his own castle’s defenses. Anyone who attacked the castle would have to get past concentric rows of fortifications, starting with an outer ditch and a fence of stakes called a palisade, while archers positioned in a high tower on the eastern end did their best to pick them off. If they got past those defenses, they were confronted by the castle’s most striking architectural feature, the 83-foot-tall, 100-square-foot Great Tower, where the castle’s inhabitants could take refuge behind walls up to 21 feet in thickness.

The soundness of those defenses was put to the test several decades after Henry II’s death. In 1216, Prince Louis of France, at the behest of rebellious English nobles, crossed the English Channel and laid siege to the castle. Louis’s forces battled past the outer defenses, and then used stone-throwing catapults, a battering ram, and finally, a team of miners who tunneled underneath one of the castle’s turrets and caused it to collapse. But despite that onslaught, they were unable to make it inside the walls, and the castle garrison, led by the intrepid Hugh de Burgh, inflicted such heavy casualties on the French that they eventually had to retreat. The defenders plugged the hole in the wall with stones and tree trunks, and the French resorted to trying to starve them out. But that didn’t work, and the siege ultimately failed. Afterward, de Burgh decided to make the castle even more formidable. He had his own miners build a network of tunnels underneath the complex, which enabled defenders to move around without being observed and to spring forth suddenly to mount surprise attacks on siege forces.

In many ways, Dover Castle exemplifies the philosophy behind medieval castles, which in some ways is similar to the defensive strategy employed by modern doomsday preppers. The ideal castle had multiple layers of defenses—ditches or moats, fences, stone walls, and towers for sentries and archers--designed to hinder a numerically superior force and allow defenders to kill as many attackers as they could. And in order to enable the inhabitants to withstand a long siege, a castle had to contain whatever they would need—from a well to supply drinking water, to a windmill to grind corn into flour, to metal-working, candle-making and pottery facilities—to survive. Often, the outer wall of a 12th or 13th Century castle featured a gatehouse, which included a drawbridge that could be pulled up to block the main entrance. Inside, there were additional barriers called portcullises—basically, the equivalent of the garage doors on a house, except that they had sharp spikes on the bottom to impale anyone who tried to slip under them as they dropped. Above the portcullises, a roof contained “murder holes” through which archers could try to pick off anyone who managed to get inside. Along the top of the gatehouse, parapets were outfitted with holes, so that guards could pour boiling oil or drop stones upon intruders.Inside the castle, there were additional layers of fortifications, including an inner wall that surrounded the central tower, or keep, a fortress-within-a-fortress where the medieval lord and his family lived. Keeps had a number of ingenious design features to thwart invaders. Their corner guard towers, for example, were outfitted with spiral staircases whose steps arose in a clockwise direction. That made it more difficult for attackers who were right-handed to use their swords.

We often think of the Middle Ages as a time when change moved slowly, if at all. But that wasn’t true of castle design. Medieval architects continually adapted to advances in siege methods, and learned from the experiences of Crusaders who tried to penetrate sophisticated Byzantine and Islamic fortifications. They also studied the examples of castles that were successfully breached. As a result, for example, they discarded the square keep design of forts such as Dover Castle, and opted for rounded towers, which didn’t have the structural weak points that could be exploited by digging beneath them. They also further reinforced the gatehouse, by adding an outer layer of fortifications called a barbican, which was set at a diagonal angle to the gate, rather than directly flush to it. That made it even more difficult for attackers to make a surprise rush to the gate and get across it.

Who knew kings and preppers had so much in common?