Skeletons dating back to the 1st Century have been discovered by archaeologists working at an Anglian Water site in Lincolnshire.
About 30 skeletons were found at The Wong
The water company called archaeologists after a geographical survey showed The Wong in Horncastle could contain important artefacts.
The archaeologists found coins, pottery, tweezers and 30 skeletons at the site.
The items have now been sent to specialists for cataloguing.
The site was originally being surveyed by the water company to see if waste water systems in the area could be improved.
Naomi Field, director of Lindsey Archaeological Services - the company called in by Anglian Water - said the find threw up some questions.
"The biggest surprise was finding the cemetery itself. We weren't as surprised about the ditches we found as aerial photographs indicated there may be some.
"But we weren't prepared for the scale of the site as the ditches are very big and deep," said Ms Field.
She added they believed the site had been a burial ground for the Roman community living in Horncastle.
The items have all been washed and have now been sent to experts for more in-depth analysis.
Anglian Water spokeswoman Collette Nicholls, said: "The find here can help plot the whereabouts of the settlement and the nature of that settlement for the very first time.
"The quality of some of the pottery found suggests the community was more than just a farming outpost."