Finds from the dig are undergoing radio carbon dating
Archaeologists have unearthed what they say could be a prehistoric Bronze Age burial site in central Oxford.
Experts say important chiefs may have been laid to rest at the site of the former Radcliffe Infirmary.
Land around the River Thames, known as the River Isis as it passes through Oxford, was often used for prehistoric burial, ritual and social monuments.
The Museum of London Archaeology (Mola) also revealed evidence of a later 6th Century Saxon settlement.
Finds from the dig are undergoing radio carbon dating.
The experts discovered traces of three large "ring ditches", which could have been Bronze Age burial sites.
A Mola spokesman said: "Ring ditches are, as the name suggests, circular ditches, which are often the remains of ploughed-out barrows, that may be associated with burials of high-status individuals in the later Neolithic or Bronze Age, about 4,000 years ago."
Saxon activity around the much earlier prehistoric barrows is not unusual and is found at other similar sites along the Thames.
The Radcliffe Infirmary site is being redeveloped as part of plans for Oxford University's new Radcliffe Observatory Quarter.
There are plans for a mathematical institute, a humanities building and a library on the site.