Engineering's Great Achievements: The Wall of Hadrian by Robert Hill

The Great Wall of England? Not quite, but the Wall of Hadrian is the greatest Roman wall in Britain. It still stands today as a monument to the Roman Empire, a complex military installation, and one of the great Roman feats of engineering. The Wall of Hadrian is a monument to the Roman Empire. Built on the Emperor Hadrian's orders in A.D. 122, it stretched across England, marking the Empire's northernmost boundary. It took six long years to build, stonily snaking its way for seventy-three miles from coast to coast. Crossing the shortest breadth of the Island, it offered the most defense for the least amount of money and men. In the West, it began at Bowness on Solway and ended at Wallsend in the East. The Wall even earned mention in Gibbon's Decline and Fall of the Roman Empire. A complex military installation, the Wall of Hadrian was very well planned. A milecastle, manned by at least eight, marked each mile. Between each pair of milecastles were two centered watchtowers, guarded by sentries. This system allowed signals to travel up and down the Wall rapidly. To the south, behind the wall, large forts housed auxiliary soldiers, clad in gleaming armor. To the north, soldiers dug a thirty-foot wide moat. Nineteen feet behind it lay the Wall itself, a considerable 9.5 feet thick and fifteen feet tall, plus six-foot crenellations, for an imposing twenty-one feet. As a complex feat of engineering, it has many strong points. First, considering the technology of the day, building a seventy-three-mile long wall is quite an accomplishment. On top of that, it wasn't just a good wall, it was an excellent wall. Second, major border disputes never really happened along the Wall. Perhaps the barbarians decided against scaling the well-defended wall. Apparently, the Romans had suitable maps to find the shortest distance necessary. The Wall has lasted for nineteen centuries: a credit to its superior structural integrity. The Wall was used, with a forty-year interruption, for almost three hundred years. Not many modern structures have been used that long. While buildings are quickly outmoded nowadays, three hundred years is still an extremely long time. Therefore, the Wall of Hadrian, or the Great Wall of England, is an amazing engineering achievement. As a tribute to the Empire, its complexity, and its sheer size, it deserves the status of the great engineering achievement.