A cluster of rare flint tools unearthed at Norwich City's football ground could date back 12,000.
The ancient flint tools could be 12,000 years old
Archaeologists have found flint artefacts on the site of a new stand at the club's Carrow Road ground.
Experts believe the tools could be from the Upper Palaeolithic era.
Archaeologists have found a sand island surrounded by peat which extends under the riverside ground.
David Adams, project manager from Norfolk Archaeological Unit, said the clusters of flint tools found in this area were left by Mesolithic people from around 10,000 years ago, but experts said they could be 12,000 years old, from 10,000 BC.
It's a very exciting find. It's older than we were hoping to find
Archaeologist David Adams
The tools were left by nomadic hunter-gatherers who would have used them to catch prey in the river valley such as reindeer when this glacial period was cold and harsh.
Mr Adams said the discoveries were rare, adding: "It's a very exciting find. It's older than we were hoping to find.
"Within Norfolk it is certainly very important and will probably be of national interest."
The archaeologists stressed their six-week dig would be finishing two weeks ahead of schedule.