The 2,000-year-old secret hidden in Chester Pret a Manger's basement

Few of the patrons drinking in Chester's Pret a Manger on busy, Northgate Street have any idea that hidden in this café's basement, in a storeroom surrounded by coffee cups and napkin boxes, are the last remnants of arguably the most important building in Chester's history.

Opposite the toilets in the café's basement, a pair of double doors are kept under lock and key. Behind their frosted glass, huge blocks of sandstone protrude through the floor, almost touching the low ceiling. Huge sandstone blocks protrude through the floor of the

One of these blocks, around four feet tall, shows the characteristic rounded lip at the base of a pillar still perfectly formed. These blocks once formed part of Chester's principia, built almost 2,000 years ago.

Rob Foulkes, 42, from Deva Roman Discovery Centre describes the function of the building: “The principia was the central administrative building and the spiritual home of the Roman soldiers here in the fortress of Deva nearly 2,000 years ago.

"It was a big place where a lot of the money was kept in a place called the Ararium, so it’s a very, very important building because otherwise the Roman soldiers wouldn’t have had their pay doled out to them.

"It was also a place where they had the aedes which is where they kept the standards. The standards were very important to the roman soldiers, and each cohort would have had their own particular standard that they would have carried into battle."

While dressed as a Roman soldier he examines the pillars in the basement of the café. He describes the scene on this spot over 1900 years ago: "This is part of a colonnaded avenue, there would have been many columns along like this … going all along about as far as the Dublin Packet.

"Just behind that is where you can see the stronghouse… where they kept the gold. That’s the thing about Chester, it’s full of stuff like this, it’s under your nose, it’s just that it’s underground or it has been moved around in places.

"One of the things that might have happened is that, after the Romans left, a lot of buildings were repurposed by the Saxons. They could have potentially used this building as an administrative centre themselves. When Aethelflaed was here, she may have used it… as a place to govern from herself."

He adds: "A lot of time, [the legion] spent a lot of time outside of Deva, and the fortress fell into quite a state of neglect, so it’s quite hard to quantify how long this would have been used as an administrative centre because Chester went through quite a bit of flux.

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