Hadrian's Wall

Hadrian’s Wall is a remarkable relic of the Roman Empire, having been in place for nearly 1900 years. The size of the wall, which stretches for 73 miles across northern England, is amazing in itself, as are the remains of various forts and other structures along its length.

Why build a wall?

The forces of the Roman Empire never conquered the whole of the island of Britain. Although the Roman general Agricola had managed to subdue the tribes of southern Scotland in AD 80 to 82, and he defeated a Caledonian army at Mons Graupius (near modern Aberdeen) in AD 83, it proved very difficult to consolidate any gains of territory that were made, and the tribes that occupied these wild lands were fiercely independent.

It was therefore decided by Emperor Hadrian (reign AD 117-138) to set a limit to the Roman Empire by building a wall across northern England, beyond which the Romans would seek no further conquests. Hadrian spent much of his reign away from Rome, particularly in the frontier provinces, and it was during a visit to Britain in AD 122 that he ordered the wall to be built and surveyed the course that it would take. It took about six years to complete, although some work was being done as late as AD 136.

The wall had a threefold purpose. One was to protect the province of Britannia from incursions by the tribes to the north. Another was to make it clear to Romans in general that the Empire was now fixed in extent and no further expansion was contemplated (Hadrian also built walls in other places, such as Germany, with the same end in view). A third function of the wall was to regulate (and thereby tax) trade between the native peoples north and south of the wall. Although the wall was a barrier it was a leaky one in that there were plenty of places where passage through it was possible.

The site of the wall

Hadrian’s Wall stretches for 73 miles (80 Roman miles) from the River Tyne in the east to the Solway Firth in the west. It comes close to the modern border between England and Scotland in the west, but the English county of Northumberland lies mainly to the north of the wall, with the Scottish border being some 60 miles north of the eastern end of the wall.

For part of its length the wall runs along the top of the Great Whin Sill, an ancient outcrop of volcanic rock that forms a north-facing scarp slope that presents a natural obstacle and also provides some of the most stunning scenery along the extent of the wall. It is fortunate for visitors that this is also where the wall is best preserved, there having been fewer people around in the intervening centuries to take the stones for their own walls and buildings.

How the wall was built

Construction of the wall was done by three Roman legions, the second, sixth and twentieth, and each had its own way of building the fortifications that are dotted along the wall. It was started at the eastern end and proceeded westwards.

Stone blocks were used for the first 42 miles (stone facing on a rubble interior), but the western 31 miles were originally built as a turf wall although stone reinforcements were added later. The wall was 15 feet high and up to 10 feet wide with a 6-foot parapet on top.

The original scheme was for a continuous wall, fronted by a ditch, with small forts built at intervals of a Roman mile. These would have gates to the north and the south, with barracks for up to 30 men. There would be small turrets at intervals of a third of a mile between each “milecastle”, these turrets being watch-towers from which soldiers would look for any activity on either side of the wall. The plan also included the establishment of a chain of larger forts along Stanegate, the road that ran south of the wall and parallel to it at a distance of about two miles. This road predated the wall by about 50 years, and there were already small forts at regular intervals along it.

However, in AD 124 the original plan was changed in that the chain of large forts was abandoned in favour of incorporating the forts into the wall itself. This meant demolishing some of the milecastles and turrets that had already been built. Twelve full-sized forts were built originally, with five more added later. When fully in operation the wall was guarded by about 9,000 men stationed along it.

The plan was also changed to include the digging of a broad and deep ditch, the “Vallum”, on the south side of the wall. This was flat-bottomed, about 21 feet wide and eight feet deep, and with a turf bank that was set back from each edge. The Vallum could only be crossed by causeways that led to the forts. The purpose of the Vallum appears to have been to control access from the south, which suggests that the presence of the wall was resented by people living in this area whose freedom to contact and trade with people to the north had been curtailed by the building of the wall.

What can you see?

Visitors to the wall today can only see the remains of what was clearly a formidable structure in its heyday. It has been estimated that some 24 million blocks of stone were used, and that the mass of the wall was greater than that of all the pyramids of Giza put together. All the work was done by hand using only primitive tools, by today’s standards, and this included the cutting of the regular-shaped stones and the digging of the Vallum, often through solid rock.

Visitors must also wonder at examples of the military mind at work, such as where milecastles were placed inappropriately because that was where they had to go, at mile intervals. There could be no other reason for a gateway that led straight to a sheer precipice!

The forts at Housesteads and Chesters are well worth a visit. That at Housesteads includes remains of granaries and barracks and a latrine block that used a form of water flushing to carry waste material out of the building. There is evidence of an extensive civilian settlement outside the walls of the fort, and ruts worn by Roman carts in the stone road can still be seen nearly 2,000 years after they were made.

A visit to the wall must also allow time to see the remains of Vindolanda (Chesterholm) which is the largest of the Stanegate forts. The original timber-built fort would have been used by the builders of Hadrian’s Wall, but it was abandoned as part of the changes made in AD 124 and only rebuilt some time later as an impressive fort and small town. The finds made here have been remarkable and include evidence of family life. Particularly fascinating have been finds of wooden tablets that were used for inscribing messages that reveal the personal lives of the people who lived here.

What happened to the wall?

Hadrian’s successor, Antoninus Pius, did not accept Hadrian’s view that the Empire must end at the wall and he tried to advance the line further north, building a new wall between the Firths of Forth and Clyde. During the 20-year period when the Antonine Wall was fortified and manned, Hadrian’s Wall was of less importance and was largely abandoned.

However, it proved impossible to defend the far less substantial Antonine Wall (built of turf on a stone base) and Emperor Marcus Aurelius abandoned it in AD 164, relying instead on the original Hadrian’s Wall as his northern boundary. Any ambitions to conquer lands north of the wall were relinquished for ever after the death (in Britain) of Septimius Severus in 211, but Hadrian’s Wall held firm until 367 when the Picts were eventually able to breach it, at the same time that Britannia was under threat from Saxons and Franks further south. Despite this breach, the wall was occupied until the final abandonment of Britannia by the Romans in 410.

As mentioned above, the fabric of much of the wall has disappeared over the centuries, with some of the stones being taken in the 18^th century for the building of roads to enable the defence of England against the Scots in the 1745 Jacobite Rebellion. More stones would undoubtedly have been lost but for the efforts of Newcastle town clerk John Clayton in the 19^th century. Clayton bought some of the land on which the wall stood and encouraged people to visit it and support its preservation, as well as restoring some portions of it.

Hadrian’s Wall is now preserved by the National Trust and is recognised by UNESCO as a World Heritage Site.

© John Welford