Archaeologists stumble across sinister skull markings and mysterious vault below historic British street

Researchers from the Canterbury Archaeological Trust were then called in to investigate the St Mary Bredman Square breakthrough.

While only a hunch, experts suspect the vault is the resting place of Reverend John Duncombe, a Vicar at St Mary Bredman church, which formerly stood at the site.

A late 18th-century description of monuments in the church describes a grave slab dedicated to Rev Duncombe.

The vicar was also a poet and wrote about archaeology.

The Canterbury Archaeological Trust said: "Whilst it’s difficult to say for certain, the position of the vault in the important eastern end of the church and the style and date of its construction lining up with the Reverend’s death in January 1786 are encouraging."

The sinister grave slab, however, is not believed to be linked to the vicar.

This design, with a carved skull and laurel wreath, is a "memento mori" design, which often includes macabre imagery including skeletons, wings, flowers, and sand timers, the Canterbury Archaeological Society said.

Fourteen vaults have been examined across three church sites in the city.

The square, which currently serves as a war memorial, is undergoing a renovation which will see trees planted and benches erected to provide respite from the high street.

A mural of a church window will also be painted to display the area's history.

Jess Twyman, one of the archaeologists at the trust, told the BBC she was fascinated by the breakthrough.

She said: "The most important thing to me is looking at people's lives, how they lived in the past."

The archaeologist, who has worked for the trust for 25 years, said others on her team were not as interested in the mysterious vault and grave slab.

Her colleague, Mark Houliston, said Canterbury had about 25 parish churches within city walls, which are now revealing their history.

The Canterbury Archaeological Trust added that renovation plans "will include the repositioning of grave markers so that these memorials are easier to view and appreciate".

"The utmost care will be taken to ensure that the memorials are treated with the respect they deserve," it added.

The Canterbury Archaeological Trust was founded in 1975 to carry out archaeological digs throughout Canterbury and Kent.

Last month, the organisation described the finding as "the closest thing to an Indiana Jones adventure" you could get.