Carefully laid out skeletons thought to be from a 14th century burial ground have been discovered during work on the London's Crossrail project.
Twelve skeletons, lying in two neat rows, were found on the edge of Charterhouse Square in Farringdon in the City of London.
Uncovered more than 8ft (2.4m) below the road that surrounds gardens in the square, the skeletons are thought to be victims of the Black Death plague which swept through Britain and Europe in 1348.
Tests will be carried out on the skeletons but experts are linking the discovery with the Black Death as it is known that a burial ground for plague victims was opened in the Farringdon area.
Limited written records suggest up to 50,000 people might have been buried in less than three years at Farringdon, with the burial ground being used up until the 1500s.
Pottery dated up until 1350 found in the graves by the Crossrail team and the layout of the skeletons all point to them being plague victims. A similar skeleton formation was found in a Black Death burial site in nearby east Smithfield in the 1980s. The skeletons are being carefully excavated and taken to the Museum of London Archaeology for testing.
Scientists are hoping to map the DNA signature of the plague virus and possibly contribute to the discussion regarding what virus caused the Black Death. The bones will also be carbon dated to try to establish when they were buried.
Crossrail lead archaeologist Jay Carver said: "This is a highly significant discovery and at the moment we are left with many questions that we hope to answer.
"We will be undertaking scientific tests on the skeletons over the coming months to establish their cause of death, whether they were plague victims from the 14th century or later residents, how old they were and perhaps evidence of who they were.
"However, at this early stage... all points towards this being part of the 14th century emergency burial ground."
These are not the first skeletons found on the Crossrail projects, with archaeologists already uncovering more than 300 at a known burial ground at Liverpool Street in London that dates from the 1500s to 1700s. That burial ground was located near the Bedlam Hospital.
Archaeologists also hope to find Roman artefacts as they dig deeper at the Farringdon site.
Once the archaeologists have finished their work, Crossrail excavators will dig the shaft down to around 65ft (19.8m) with the site to be used to support tunnelling works.
Once analysis of the bones has been completed, the skeletons will be reburied on the site or other cemetery.
Around 1.5 million Britons died in the Black Death - more than a third of the population - and in Europe about 25 million perished.
These are not the first skeletons found on the Crossrail projects, with archaeologists already uncovering more than 300 burials at the New Cemetery near the site of the Bedlam Hospital at Liverpool Street from the 1500s to 1700s.
At £14.8 billion, Crossrail is the biggest construction project in Europe, building a 118 kilometre rail line and 42km of underground lines.
Much of this work is being done underground, right under the feet of oblivious Londoners.
Five tunnel boring machines (TBMs), each one weighing 1,000 tonnes and 148m long, are currently underneath the capital's streets chewing through the earth at a snail-like 100m a week.
Some more Crossrail facts:
- Eight new underground stations at Paddington, Bond Street, Tottenham Court Road, Farringdon, Liverpool Street, Whitechapel, Canary Wharf and Woolwich will be built
- A new surface station will also be constructed at Custom House
- Crossrail will increase the capacity of London’s rail based public transport network by 10 per cent
- An estimated 200 million people will travel on Crossrail each year
- Phyllis (one of the TBMs) is currently under Hyde Park having completed 2.9km of tunnel and is now heading for Crossrail’s Bond Street Station western ticket hall in Davies Street
- At least two-thirds of all Crossrail excavated material, more than 4.5m tonnes, will be used to create the new RSPB nature reserve at Wallasea Island, creating Europe’s largest man-made coastal reserve