Inside the bottle was a message on paper, rolled up and tied with string.

On Tuesday evening, Mr Blondel opened the paper – which read as follows:

“P.J Féret, a native of Dieppe, member of various intellectual societies, carried out excavations here in January 1825. He continues his investigations in this vast area known as the Cité de Limes or Caesar’s Camp.”

Féret was a local notable, and municipal records confirm that he conducted a first dig at the site 200 years ago.