SLEEPING under a Swindon bypass is a Roman city that archaeologists say is twice as big as they first thought.

The site, to the east of the A419 near Covingham, has been known about since the 18th century when it was referred to by well-known antiquarian William Stukeley.

Bryn Walters, director of the Association of Roman Archaeology in Swindon, and archaeologist Bernard Phillips have been keeping the hidden town under observation for years.

They have discovered it had homes, shops, a temple and a mansio, which was an imperial lodging house.

Bryn said: “It is a cursus publicus, which is like a motel for imperial civil servants scurrying about on government business. It is one of the first mansios unexcavated in Britain and sadly it is now under a pick your own farm.’’ The core of the Roman town is protected as a Schedule Ancient Monument, which has caused problems with erecting sound barriers alongside the busy A419 at Covingham, because there are burial sites there.

Bernard was there in 1967 when they first found the burial sites. He said: “We found cremations as well as burials which dated from early second to fifth century.”

He came across some extraordinary finds, including a skeleton of a man aged 35 to 45 with a purse and a silver coin still attached to the pelvis.

“The head on the coin was Emperor Magnus Maximus, AD 383-388,’’ he said.

“We also uncovered evidence of a lot of arthritis of the spine in our finds and they had well worn teeth where they would grind the grain between stones and then eat the bread with stone in it.”

When the A419 bypass to the M4 motorway was built, a lot of the Roman town was lost.

“The bulldozers smashed through some impressive buildings including a polygonal temple by the bridge,’’ said Bryn.

“We saw part of the 3ft high walls and the white tessellated floors, like mosaics. There were also fine blocks 6ft thick which were part of an outer wall or gateway. It is a tragedy this was lost.”

Swindon today is on the M4 corridor with easy access to London, Bristol and Bath and it was the same in Roman times as Ermin Street was the main road leading from Londinium (London) to Corinium (Cirencester) and at the apex of three tribes.

In the south were the Atrebates, to the South West were the Belgae and our own tribe would have been in the North, called Dobunori.