Archaeologists have discovered what they believe to be the remains of a Roman villa and bathhouse on land earmarked for a supermarket.
The discovery, featuring mosaic stonework, was found in Warrington Road in Olney, Buckinghamshire.
The site is being prepared for the construction of a new Aldi supermarket.
Oxford Archaeology, who carried out the work for developer Angle Property, considered the mosaic to be “archaeological remains of great significance”.
Archaeologists said the mosaic featured “vibrant colors and intricate decorative patterns” made up of red, white and blue tiles.
Many of the ancient works are believed to extend below Warrington Road and so cannot be fully explored, the archaeological team said.
Oxford Archeology said after consultation with Historic England and Milton Keynes Council, the mosaic has been preserved in situ.
It means that materials have been placed over the masonry to protect it, but construction can continue without damage.
John Boothroyd, senior project manager at Oxford Archaeology, said: “We expected some remarkable Roman remains due to the location, but the discovery of this fantastic mosaic far exceeded those expectations.
“To be able to preserve vestiges of this quality and importance is a brilliant achievement, and one that could only have been achieved with the support of Angle Property.”
Anthony Williamson, executive director of Angle Property, said the find had “surprised us all” and promised it will be “fully recorded” and information about it will be published.
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