It is the largest monument from the ancient era in northern Europe, but Hadrian's Wall in fact has an older and more northern brother.
Archaeologists have been carrying out research into a huge late fist century AD defence system, which stretches 120 miles across Scotland.
A total of 14 forts and several fortlets, which formed part of a defensive network built in the AD 70s, have so far been investigated over the past decade by the team, led by Dr Birgitta Hoffmann and Dr David Wolliscroft, both of the University of Liverpool.
Archaeologists have been carrying out research into a huge defence system, which is believed to have been built in the AD 70s and stretches 120 miles across Scotland
The structure is not believed to be a continuous wall or ditch, but instead consist of 20 forts, a dozen fortlets and up to 30 watchtowers in total, the BBC History Magazine has reported.
The network, which is thought to have run from Montrose or Stonehaven, south of Aberdeen, on the North Sea coast to the Firth or Clyde, was built some 50 years before Hadrian's Wall, and is an extra 20 years older than Antonine Wall.
The team, who have carried out surveys of seven of the largest forts over the last five years, are hunting for the missing fortlets and towers. The forts are believed to have been manned by more troops than previously thought and it is also believed many were cavalry units.
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The BBC has reported the defensive line was built by the Romans in an attempt to keep hold of the land they had invaded in around 69 or 70 Ad from hostile northern Caledonian tribes.
It also thought however that the fortress protected the friendly lowland tribes from cattle-raiders, fostering good relations which led to large civilian settlements being set up near the forts.
According to the BBC, these settlements could have been made up of merchants, craftsmen and possibly girlfriends of the troops.
Hadrian's Wall (pictured) is the largest monument from the ancient era in northern Europe, but archaeologists have been carrying out research into its older brother
Hadrian's Wall remained in use until the early fifth century
Although the Romans in Scotland had good relations with many of the locals, they did have tensions with the northern Caledonian tribes, which is thought to have eventually erupted into major conflict in AD 83 or 84.
It is thought the two sides clashed at the battle of 'Mons Graupis', with up to 30,000 men fighting on either side.
The precise location of the battle is still unknown, however it is possible the research along the Scottish fortress, abandoned by the Romans in about AD 87, could lead to its discovery.
MONUMENT FROM THE ANCIENT ERA
Hadrian's Wall, which stretches across northern England, was built in 122 AD on the orders of the Roman emperor Hadrian to mark his empire's northern frontier.
It took eight years to build the 73 mile-long wall from the Solway Firth to Wallsend on the Tyne.
It is believed to have provided a barrier between Roman Britain and Scotland and is thought to have been where the army could determine who was allowed access to the empire.
It remained in use until the early fifth century when, with the empire collapsing and the city of Rome itself under threat, the Romans left British shores.
It is the largest monument from the ancient era in northern Europe and is a UNESCO World Heritage Site.
When Emperor Hadrian built Hadrian's Wall nearly 2,000 years ago, it extended 73 miles coast to coast across northern England from the Solway Firth to Wallsend on the Tyne.
Standing 16ft high and up to 12ft wide, it was an extraordinary feat of engineering which was completed in eight years.
It was built in AD 122 after Emperor Hadrian ordered his soldiers to build a barrier between Roman Britain and Scotland.
According to the Hadrian's Wall Trust, a chief function of the wall was probably frontier control, where the army enforced the regulations which determined access to the empire.
It is believed people could only enter the empire at certain points and would have been forced to travel unarmed and under military escort to markets or other specified places.
It is also believed to have helped to prevent raiding.
It was believed to have been the first of two fortifications built across Great Britain. The Antonine Wall, however, is the lesser known of the two because its physical remains are less evident.
As well as being a strong military fortification, it is believed the wall featured a number of gates which would have served as customs posts.It is the largest monument from the ancient era in northern Europe and is a UNESCO World Heritage Site.