It's Carlisle's most exciting Roman find for decades.

When a team of seasoned archaeologists began their exploratory dig at Carlisle Cricket Club's Edenside ground two weeks ago, they had little expectation that they would uncover anything truly exceptional.

Club officials commissioned the dig because they want to build a new pavilion. The dig was a necessary part of preparing the project.

As the team from archaeology contractor Wardell Armstrong got to work, digging a trench in what had been an old tennis court, they got their first glimpse of a wall, its rough sandstone blocks arranged in a long, sweeping curve.

It was the start of a two week archaeology roller coaster.

For this unpromising site then began to yield its secrets, revealing a fantastically preserved and sophisticated bath house that was once a popular meeting place for members of the Ala Petriana cavalry regiment based in Stanwix.

When his phone rang and his colleagues told him what they'd found, Wardell Armstong technical director Frank Giecco was so excited that he cancelled his day off and rushed to the cricket ground.

“It's a highly significant find,” says Frank.

“We'd never known where the bath-house was for the cavalry fort. It would have been a very important part of life for these troops. There were 1,000 of them based at Stanwix and they were paid more money than other Roman soldiers.”

The Roman Empire's most elite guardians on its empire's northernmost frontier, the Ala Petriana troops were feared and respected. The bath-house that has emerged at the cricket ground throws a fascinating light on their life.

Frank says: “The bath house was a very important meeting place for the cavalrymen – and there would have been a lot of gambling here.”

As the archaeology team worked at the site, painstakingly exposing a past that lay hidden for nearly two millennia, there was a palpable excitement: the catalogue of discoveries grew steadily over the life of the dig.

First came evidence of a superbly sophisticated bath-house building, complete with its own 'hypocaust', the Roman equivalent of underfloor-heating.

There are distinctly blackened areas of stonework, evidence of the furnaces that once heated the bath house water.

Hollow wall tiles distributed the hot air to keep the air pleasant for the bathing soldiers.

The team also found entire rooms, the floor neatly finished off with the Roman version of waterproof concrete, called opus signatum.

But the dig has uncovered so much more – including an iron arrow head, bone hairpins (suggesting women were allowed into the bath house), pottery, more than 100 superbly preserved coins from the second and third century.

There were also fragments of still gleaming scale armour, used by the soldiers in their dangerous work along Hadrian's Wall.

For Wardell Armstrong's newest recruit, 21-year-old Durham University graduate Rachel Frame, the dig was a career milestone: it saw her unearth her first Roman coin, a beautifully preserved silver denarius, bearing the image of Julia Domna.

The wife of Emperor Lucius Septimus Severus, and an Empress in her own right, Domna was part of an an aristocratic family of priest kings. She wielded immense political influence, and joined the Emperor as he launched a campaign against the Britons in 208.

“I was super excited all day,” says Rachel.

“I did archaeology at Durham, and classics, Latin, and Greek all through school. It's exciting to be working on a site like this. A lot of the coins are really well preserved.”

Rachel holds up a tiny silver coin, its face decorated with an image of Diana, the Roman goddess of hunting, her slender body draped in elegant, flowing fabric, and a bow and arrow held in her hands.

“It's like it was minted yesterday,” says Rachel, beaming. “You can read every bit of the writing on it because it's in such a good state of preservation. It's really exciting. To find something this important when nobody knew it was here is amazing.”

Another highlight of the dig came when veteran archaeology worker Alan James uncovered what some regard as the site's most impressive find – a sandstone block inscribed with a tribute to Julia Domna.

Its message suggests it was clearly written after the death of her husband Severus and while her son Caracalla was Emperor.

Crisp and unweathered, the Roman letters look freshly carved, their message paying fulsome tribute to Domna as the mother of the Emperor, mother of the Roman nation, and mother of Army.

The dig itself was led by Kevin Mounsey.

He says: “There was little expectation when we started. Finds like this are rare – it's Premiere League archaeology. Nobody knew there was anything like this down here. I've been doing this job for 12 years.

“This dig is probably the best ever.

“It would be great if the whole site could be opened up and something permanent could be created here. Carlisle doesn't have much in the way of standing Roman remains, but that's for others to decide.”

That vision for something more enduring – a permanent display that would bring to life Carlisle's Roman past – is shared by both the owners of the cricket ground and by Carlisle City Council Leader Colin Glover.

He was so impressed by the finds that the Council awarded the dig a £6,000 grant to extend the dig for a second week.

He says: “The archaeology they've found is absolutely stunning. “It's been a dream for a long time to find Roman archaeology in Carlisle that is good enough to show to the public. What they've found at the Cricket Club site is really stunning: there are whole rooms, surviving Roman floors, parts of cooking pots, including one with a lion's head through which sauces would be poured.”

With support from the Heritage Lottery Fund, the project could have the potential to do for Carlisle what Viking history did for York, suggests Mr Glover.

Mike Rayson, chairman of Carlisle Cricket Club, adds: “I hope that the site can be opened up. It's a really significant find. As Frank Giecco said, this is the kind of history you come across once in a lifetime.”