Tuesday, 26th May 2009 by RobK
When the Romans invaded Britain in the 1st century AD, they never quite managed to conquer Caledonia – the area now known as Scotland.
We’ll never know whether the Roman army felt it was too much like hard work to defeat the fearsome northern tribes, or were simply under-attired for the fearsome Scottish weather; either way, in AD 122 the Roman Emperor Hadrian ordered the construction of a wall to defend his territory from the lands to the north.
Hadrian’s Wall stretched for 80 Roman miles (73.5 modern-day miles, or 117km), from the Solway Firth (where the wall is still visible) to the River Tyne (where the wall has vanished, but the fort of Segedunum, which marked its eastern end, has been excavated).
Despite being almost 2,000 years old (and having been heavily plundered by the locals for building materials after the Romans left), a surprising amount of the wall can still be seen today. One of the best preserved stretches is near the village of Gilsland. Here you can also see the foundations of the Roman bridge across the River Irthing – although since it was built the course of the river has shifted westwards.
There are an astonishing number of Roman sites in this area, as a look at the Ordnance Survey map shows. Among them are Birdoswald fort; the nicely preserved milecastle 481 (right next to the spot where the railway line slices through the wall); and a couple of Roman camps. The shadows on the aerial photography really show up the traces of old structures and ditches, even where there is little else left on the ground.
The wall was not a single structure: at various stages in its history it was extended, and separate banks and ditches added. Among the later additions was the Vallum, consisting of three earth banks separated by ditches, running parallel to the wall a few hundred metres to the south. The surviving stretches also show up well in aerial imagery; if you scroll northwards from this point you can see the wall itself.
In many places, the builders used the natural topography to help create a formidable barrier. One spectacular stretch of wall follows a steep rocky ridge, Highshield Crags.
The low angle of the sun creates some dramatic shadows here – and if you zoom right in, you can see the shadow of a sycamore tree in the hollow between two ridges. This location, known as Sycamore Gap, will be familiar to fans of the film Robin Hood: Prince of Thieves: it’s the spot where Kevin Costner rescued a small boy from the dastardly Guy of Gisbourne.2