PLANNED repairs to the central heating of a church have uncovered remains suggesting it may have been used as a place of worship in prehistoric times.
Archaeologists now believe the medieval church of St Michaels and All Angels, in Houghton-le-Spring, Wearside, is on the site of earlier places of worship, possibly dating from the Neolithic period.
Old burial grounds have been unearthed during work by the Archaeology Practice, but it has also revealed foundations of previous churches on the site.
Stones uncovered beneath the church floor are thought to have been part of a Roman building, while there is also evidence of prehistoric activity in the area.
Peter Ryder has led the three-man team carrying out excavations before a major refurbishment, which will include replacing the central heating system and restoration of much of the stonework.
He said the site appears to have been a place of worship long before the existing medieval church was built.
"It's thought the first church here was late Saxon or early Norman, but there's strong evidence of a prehistoric ritual site.
"We've found big boulders, and during earlier work under the church yard, there was a line of stones, which is clearly a significant archaeological feature.
"The boulders are probably prehistoric and there are large blocks of stone from an early structure, which could be Roman.
"I have never seen them in a medieval structure, although a sarcophagus, a stone tomb with a lid, which looks Roman was found under the church yard."