Archaeologists say they have uncovered Britain's "Pompeii" after discovering the "best-preserved Bronze Age dwellings ever found" in the country.
The circular wooden houses, built on stilts, form part of a settlement at Must Farm quarry, in Cambridgeshire, and date to about 1000-800 BC.
A fire destroyed the posts, causing the houses to fall into a river where silt helped preserve the contents.
Pots with meals still inside have been found at the site.
An earlier test trench at the site, near Whittlesey, revealed small cups, bowls and jars.
In addition, archaeologists said "exotic" glass beads that formed part of a necklace "hinted at a sophistication not usually associated with the Bronze Age".
Textiles made from plant fibres such as lime tree bark have also been unearthed.
However, the roundhouses themselves are now being excavated.
Archaeologists think they have found about five houses but are not yet certain.
Bronze Age Europe and Britain
- The Bronze Age in Britain lasted from between 2500 and 2000BC until the use of iron became common, between 800-650BC
- It came after metalworkers discovered that adding tin to copper produced bronze, used for tools and weaponry which were much more hard-wearing
- The Greek poems of Homer - though composed later - look back to a time when bronze weapons were used
- In Britain, the Bronze Age lasted until about 800BC. Use of bronze seems to have coincided with fresh migration of people from the continent.
- Classic Bronze Age remains include sophisticated axes, precious gold objects, and round burial mounds or "barrows" of which many can still be seen in Britain
The work to uncover the settlement is necessary because there are concerns the water level at the site could fall some time in the future, meaning the remains of the houses cannot be preserved in situ.
Duncan Wilson, chief executive of Historic England, which is jointly funding the excavation with land owner Forterra, described the settlement and contents as "an extraordinary time capsule".
He added: "A dramatic fire 3,000 years ago, combined with subsequent waterlogged preservation, has left to us a frozen moment in time, which gives us a graphic picture of life in the Bronze Age.
"This site is of international significance and its excavation really will transform our understanding of the period."
David Gibson, from Cambridge Archaeological Unit, which is leading the excavation, said: "So much has been preserved, we can actually see everyday life during the Bronze Age in the round.
"It's prehistoric archaeology in 3D, with an unsurpassed finds assemblage both in terms of range and quantity."
Well-preserved charred roof timbers of one of the roundhouses are clearly visible, together with timbers showing tool marks and a perimeter of wooden posts known as a palisade, which once enclosed the site.
While a number of Bronze Age settlements have been found in the UK, Mr Gibson said none had been as well-preserved as the Must Farm site.
"Most don't have any timber remaining, just post-holes and marks where posts would have been," he said.
"So far this is unique as we have the roof structure as well."
He said there were some well-preserved similar dwellings at Loch Tay in Perthshire, but these were about 500 years later than those in Cambridgeshire, dating from the early Iron Age.
Archaeologists digging two metres (6ft) below the modern surface at the quarry also found preserved footprints, believed to be from people who once lived there.
Once all the retrieved items have been cleaned and documented they are expected to be put on public display.