Excavations have uncovered remains of a large Roman villa complex, revealing previously unknown details of the inhabitants of Sussex almost 2,000 years ago.

Teams of archaeologists and students are working in a cornfield near Lewes in one of the largest archaeological digs currently taking place in Britain.

The exact location of the dig has been kept secret in recent weeks for fear of the tightly controlled site being overrun by unauthorised treasure seekers.

The villa is believed to be one of the largest Roman complexes of its type found in Britain. Even those working on the site are surprised at the extent of it.

The dig has discovered a ten-room house, which, at the time, was possibly the largest building in the Lewes area as well as an array of outbuildings.

Experts say it gives a valuable insight into the way settlers in Sussex traded and welcomed the Romans after they invaded Britain in 43AD.

It is clear from unearthed mosaic tiles, a number of oyster shelves and the layout of the building that the house was occupied by a wealthy family.

The site has 24 archaeologists and students working on it. Although nearby residents know of the dig, few realise the significance of the find, which even those on the site want to keep secret.

Pottery, mosaics and small tools have been found.

The excavations show the site was occupied from about 50AD to 300AD.

The archaeologists and students, some of whom have flown in from other parts of the world, are involved in a race against time to map out the extent of the settlement.

The dig will be come to an end shortly when the field, overlooking the Ouse Valley, will revert to agricultural use. Bulldozers are ready to move in and cover up the site.

Chris Butler, of the Mid Sussex Archaeological Team, and students from the University College of London have been planning the dig for more than a year.

They have spent the past few weeks encamped in the large field as they dig down just under three feet to reveal the foundations and the walls of the large villa and its outbuildings.

It has been known for several years there was some kind of settlement beneath the soil in what was otherwise a perfectly ordinary spot.

Mr Butler said: "Pieces of pottery had been churned up over the years by farmers.

"It was known there was something underneath the surface but nobody knew exactly what."

A resitivity test showed there was a large building just beneath the earth.

Resitivity works by passing an electric current through the ground. When it hits a wall there is a high resistance and when there is a space there is a low resistance.

The results were fed into a computer giving the team some idea of what they were looking for. But as soon as they started digging, they discovered the site was bigger than they had first thought.

There is evidence people were living in an area of 140ft by 80ft, with the villa itself covering an area of between 120ft by 60ft.

Clear evidence has been found of the flint walls and various dividing walls which made up the rooms.

Drawings are being made of the building so its history will never be forgotten.

Mr Butler said: "This was a large family home. It was built here almost certainly for the views and its position.

"There were Roman roads to the north and west and this is good agriculture land.

"We thought at first the site would have been completely destroyed by years of ploughing but it has survived extremely well.

"There were ten rooms, all linked via corridors. This was probably the home of a wealthy family who had accepted the Roman invasion and decided to trade with them.

"There is evidence of mosaics and pottery, so whoever lived here was enjoying a high standard of living and they collected oysters from the river.

"There was probably someone living on the site before the Roman invasion and, when the Romans arrived, they traded with them and probably did very well.

"There is clear evidence of occupation from 50AD until 300AD. The villa was constructed of flint and timber and was two stories high.

"After about 300AD, the house fell into disrepair and there is evidence the flints were used to build a nearby church."

Extensive plans are being made and photographs of the site will be used in a permanent exhibition in Lewes.