Hadrian's Wall was abandoned by Hadrian's successor, Antoninius Pius, who, not to be outdone, built his very own Antonine Wall across central Scotland in 142. This turf wall ran for about 70 kilometres and had a lot more forts than Hadrian's Wall. However, Pius was unable to conquer the northern tribes and so when Marcus Aurelius became emperor, he abandoned the Antonine Wall and occupied Hadrian's Wall once again in AD 164. It remained occupied by Roman troops until their withdrawal from Britain.

End of an era

Its downfall started in the late 4th century AD when Barbarian invasions, economic decline and military coups loosened the Roman Empire's hold on Britain. By 410, the Roman administration and its legions were gone, and Britain was left to look after its own defences and government. The troops stationed along the wall, by now largely made up of local Briton stragglers who had nowhere else to go, probably lingered on in some form for generations.

Stones on the move

Over the centuries, lots of the stones from Hadrian's Wall have been pinched and used for constructing other local buildings. This started pretty early on. After the Empire collapsed, people tried to carry on living Roman lives but without the means to do so. One leader built himself a longhouse at one of the forts reusing some of the stones from the wall, trying to maintain the fiction.

By the Middle Ages, bishops and abbots were among those helping themselves to the nicely-cut pieces of stone to reuse, and later light-fingered farmers also used Hadrian's Wall as a gigantic quarry. Portions ended up being taken to build houses, roads and other walls, and this continued until the 20th century. In fact, most of the stones are no longer on the wall but built into surrounding field boundaries and farmhouses!

Making their mark

One example is Holmhead Guest House, a former farmhouse which stands on the foundations of Hadrian's Wall in the southwest corner of Northumberland National Park. Built in around 1800, two inscribed Roman stones have been discovered in its walls. One says "Civitas Dumnomi", indicating that a tribe from the Devon and Dorset area had been working on Hadrian's Wall, and the second stone’s inscription says "IVL.IANAL". This refers to Julius Lanalis, a Roman centurion responsible for overseeing the building of a stretch of the wall in about AD 125.

From the late 18th century, antiquarians began to study the wall, collecting sculptures and excavating. But Hero of the Wall must be lawyer and scholar John Clayton (1792-1890). He actually bought up land to save stretches of the wall from any more "recycling". He also owned five Roman forts – surely a world record!