The castle makes the feudal ages possible. It is because western Europe is covered with thousands of strongholds, each of which can stand off a considerable army, that we have the secular institutions of the thirteenth century. To be the owner and lord of at least one castle is the dream of every nobleman, and in fact until he can hoist his own banner from his own donjon he hardly has a defined place in the feudal hierarchy. [Sidenote: The Castle of St. Aliquis] As we have seen, the castle of St. Aliquis is now nearly three hundred and fifty years old. Since it has been continuously inhabited by enterprising owners, its structure has been as continuously changing. However, if we had come to the barony only fifty years ago, we would have found a decidedly primitive structure. The general plan of Heribert's original stronghold was then still retained: first, on the landward side of the triangle above the two converging rivers there was a rather deep moat, next a parapet whereof the lower part was made of earth taken from this same moat, and upon the mound rose a strong palisade of tree trunks. Within the palisade were barns, outbuildings, and barracks for such of the baron's men as did not live in the inner stronghold. Then last of all was the donjon, the castle proper--a huge square tower built with little art, but which defied attack by mere solidity. The entrance to this grim tower was by a steep inclined plane leading to a small door in the second story. In case of danger, if the palisade were forced, the seigneur and his men retreated into the tower, knocked down the wooden gangway, and shouted defiance to the enemy. The mass and height of the donjon baffled any ordinary methods of attack save that of blockade and starvation--and there would be six months' supply of wheat, salt beef, and ale in the tower vaults. [Illustration: TYPICAL CASTLE OF THE MIDDLE AGES (Without large barbican court)]