The Emperor Hadrian ordered the building of his famous wall during a visit to Britain in 122.
The Emperor Hadrian ordered the building of his famous wall during a visit to Britain in 122.
He intended it to be an imposing frontier to stop the barbarian tribes of the North raiding the wealthier lands further south.
The brick wall was built by Roman soldiers and probably took about 16 years to complete.
Once finished, it was about 6½ metres high. But a deep ditch about nine metres wide was dug on its northern side to make the barrier even more formidable.
The building of the wall was a powerful symbol of Rome’s military might – and a sign that they were in Britain to stay.
Following the invasion of 43 the Romans had swiftly set about stamping out resistance from Celtic tribes in southern Britain.
Emperor Claudius sent about 40,000 soldiers to the new province and by a mixture of brute force and clever diplomacy they soon achieved their aims.
At first the Roman frontier stretched along the line of the Rivers Severn and Trent. Most of modern-day Wales, northern England and Scotland were unconquered.
But the Romans had no intention of allowing these areas to remain under Celtic control for long.
They were particularly keen to get their hands on the mineral deposits – lead, iron, copper and even gold and silver – that the Celts mined in the West and North.
The second phase of the invasion began some ten years after the revolt of Boadicea.
By 78 the Romans had subdued Wales and pushed their frontier north to the River Tyne.
In the following six years the Roman governor Agricola launched his army into Scotland, penetrating even into the islands and highlands and inflicting heavy defeats on the Caledonian tribes.
But Scotland was never properly subdued. Over the next 40 years a bitter guerrilla war was fought out in the glens.
Time after time, the Caledonian tribesmen would strike at isolated Roman forts, then melt away into the mountains before reinforcements could arrive.
Then in 117 Hadrian became the new Emperor, ushering in a totally new strategy for the Roman Empire.
He abandoned his predecessors’ policy of expansion in favour of an empire with strictly-defined borders.
One of these would be a massive wall across Britain between the Solway Firth in the West and the River Tyne in the East.
A Roman historian, writing a life of Hadrian, later said the Emperor wanted the wall “to separate Romans from Barbarians”.
At the time Hadrian’s Wall was a state-of-the art piece of military engineering.
At every mile there was a milecastle guarded by at least eight men.
Between milecastles were two turrets. These enabled the soldiers to keep a close watch on the movement of goods, people and animals across the frontier.
In about 140 Rome again attempted to push north, establishing a new frontier in Scotland known as the Antonine Wall.
It was built of turf and stretched about 40 miles from the Firth of Forth to the Firth of Clyde.
But within 20 years the Antonine Wall – named after the Emperor Antoninus Pius – had been abandoned and the legionaries had returned to Hadrian’s Wall.
For the next two centuries Hadrian’s Wall remained Rome’s imposing northern frontier, repelling raids from a new barbarian menace, the Picts.
Then in 410 the Romans pulled out of Britain, leaving the wall as testimony to their greatness.