As part of an unfortunate attempt to expand imperial control across Britain, archaeologists have discovered the foundations of a ‘lost’ second-century Roman fort in western Scotland.

According to Historic Environment Scotland, the castle was one of 41 fortifications built along the Antonine Wall, a fortification made mostly of earthworks and wood, that stretched nearly 40 miles (65 kilometers) across Scotland at its narrowest point.

Roman Emperor Antoninus Pius ordered the wall to be built in AD 142, hoping to surpass his predecessor Hadrian, who had built a fortification about 100 miles (160 km) to the south about 20 years ago, known as Hadrian’s Wall.

However, his effort ultimately failed, in part due to hostility from the natives. (The Romans called them “Caledonians” at the time; they would later be called “Picts” from the Latin word for “painted people” because of their body design or tattoo.) After 20 years of trying to keep new ones on their northern line, the Romans ‘Wall of the Antonines’ in AD 162. They left the Wall and retreated to Hadrian’s Wall.

“Antoninus Pius was a de facto bureaucrat,” said historian and archaeologist John Reid. “He had no military experience and we think he was looking for a victory he could guarantee against the exotic Caledonian people.”

Reid declared that Roman emperors should claim military victory, and so Antoninus Pius used his conquest of Scotland to justify his rule – while he was still going.

“Lost” castle

Archaeologists from HES have discovered the buried remains of a small castle or ‘castle’ near a school at the northwest end of the modern city of Glasgow.

The building was mentioned by an antique dealer in 1707, but has not been found since, despite efforts to locate it in the 1970s and 1980s.

The castle consisted of two small wooden buildings, built on the south side of the Antonine Wall, surrounded by a stone and grass wall up to 2 meters high. The wall had two wooden towers above the gate in opposite directions – one to the north to allow people, animals and cars to pass through the wall, and the other to the south.

But now there is nothing to indicate that the castle was once there; and archaeologists found buried stone foundations using gradiometry, a non-invasive geophysical technique that measures tiny fluctuations in Earth’s magnetic field to reveal underground structures.

About 12 soldiers, many of whom were “auxilia”, enlisted to fight alongside local aides or Romans, would be stationed at the fort for about a week to monitor the terrain and prevent raids on the fortifications.

They will then be replaced by a new detachment of soldiers from the larger Roman fort at Duntocher, about a mile (1.6 km) east, according to a HES statement.

roman wall

There is now little visible evidence of the Antonine Wall, and the recently discovered fortress is a rare find.

Reed said this helped support the theory that the Romans originally hoped to replicate Hadrian’s Wall with stronger and higher stone fortifications and a small fort or “mile fort” along each mile along its length. “But then they thought about it and decided they needed the right size forts,” he said.

Roman fortifications in the Tayside area north of the Antonine Wall indicated that the Romans planned to subjugate all of Scotland, but the Antoninus Wall and all northern lands appear to have been abandoned after 162 AD.

After that, Hadrian’s Wall became the empire’s northernmost border, presumably until the fall of Roman rule in Britain in the early fifth century, he said.

The Reid Trimontium Trust excavated Burnswark Hill, where the Caledonian fortress and fortified Roman military camp are located, after Antoninus Pius ordered his legions to conquer Scotland north of Hadrian’s Wall. Among the finds were whistling shells that the Romans may have used as “weapons of terror” against the defenders.

It is not entirely clear why the Romans ultimately withdrew from the Antonine Wall and retreated to Hadrian’s Wall.

“There’s a lot of controversy,” Reid said. “Is it because the Romans are fed up? Is it because the Romans have problems elsewhere? Is it because it’s too expensive to cross two borders? Or because Antony Pius is dead? [у 161 році нашої ери]? Nobody is sure; I suspect it’s a combination of all these.’