Remains of at least six people and the corner of a building believed to date back almost 1,400 years have been uncovered by archaeologists in an alley behind Gladstone Street.
They are believed to be from Anglo-Saxon times when Hartlepool was home to one of the most important monasteries in the North of England.
Council workmen uncovered some bones close to the surface when they went to lay the foundations for a new wall after the old one collapsed during strong winds last year.
Robin Daniels, of Tees Archaeology, said: “We have been on site and excavating and found remains for at least six individuals.
“They almost certainly date from the Saxon period, which is anywhere from 650 AD to 800 AD.
“They seemed to be up against a stone structure, which suggests it may be a little chapel or something like that.
“It is almost certainly part of the monastery that became St Hilda’s. We don’t think these remains are monks however, as there are at least two children and one female.
“The cemetery is probably for ordinary people but they are there because they want to be close to the monastery.”
According to records, the monastery at Hartlepool named Heruteu – meaning the island of the hart or stag – was founded by the nun Heiu in the 640s AD shortly after Lindisfarne and before Whitby.