Thursday, October 23

The Roman Wall

Here is Hadrian's Wall at Housteads. In '98 I walked the Wall with Stan and Sonnet while Silver smacked the damn thing before returning to the car. She was well satisfied, I do recall.

Hadrian's Wall was built following a visit by Hadrian 122 at a time when he was having military difficulties in Romain Britain and from the peoples of various conquered lands across the Empire. However the construction of such an impressive wall was probably also a symbol of Roman power, both in occupied Britain and in Rome. Construction probably started in 122 and completed within six years. The route chosen parallels Stanegate road from Carlisle to Corbridge which was already defended by a system of forts, and was constructed to prevent entrance by small bands of raiders or unwanted immigration from the north, not as a fighting line for a major invasion.

The initial plan called for a ditch and wall with eighty small gated milecastle fortlets, one placed every Roman mile, holding a few dozen troops each, and pairs of evenly spaced intermediate turrets used for observation and signalling. Local limestone was used in the construction while the milecastles from timber and earth; turrets were always made from stone. Construction was divided into lengths of about 8 Km. One group of each legion would excavate the foundations and build the milecastles and turrets and then other cohorts would follow with the wall construction.

Early in its construction, just after reaching the North Tyne, the width of the wall was narrowed to 2.5 metres or even less. Within a few years it was decided to add a total of 14 to 17 full-sized forts along the length of the wall, including Houseteads, holding between 500 and 1,000 auxiliary troops. Some of the larger forts along the wall were built on top of the footings of milecastles or turrets, showing the change of plan.

After the forts had been added the Vallum was built on the southern side. It consisted of a large, flat-bottomed ditch six metres wide at the top and three metres deep bounded by a berm on each side 10 metres wide. Beyond the berms were earth banks six metres wide and two metres high. Causeways crossed the ditch at regular intervals. Initially the berm appears to have been the main route for transportation along the wall.

Abbreviated notes from Wikipedia.

PS: the Wall is 80 Roman miles or 117 kilometres long.