Archaeologists have been left mystified by the discovery that lies beneath Province House in Halifax, Nova Scotia due to the building’s blueprints and plans having no record of its existence.
It was unveiled underneath Canada’s longest-serving parliament building, a mere meters from where politicians lay down the law.
Its discovery was made purely by coincidence after an archaeological assessment of the grounds was commissioned ahead of a second remodel.
Province House is said to date back to 1811 and had replaced an earlier mansion built in 1749 for Edward Cornwallis, the British governor of Nova Scotia and founder of the city.
Further leading experts to believe the vault could be from the late 1700s or very early 1800s.
April MacIntyre, the principal archaeologist behind the assessment and discovery has described the vaults as “a complete surprise”.
In the revealing video, the rectangular vault features that it has walls of piled stone and a floor that is largely hidden beneath a layer of silt.
Thick hanging roots are seen dangling from the ceiling of the room, thought to be five metres by four metres in size.
April said: “We have not been able to find any record, or any maps or images depicting a structure at this location.
“We do know that there were several outbuildings on the property in the late 18th and early 19th centuries, but all indications are that this was a subterranean structure with no superstructure.
“As to the function of the structure, we cannot say with any certainty.
“Due to safety issues, we were only able to observe the feature from the outside, via the small opening that had been broken open at the top.
“It appears that there was an opening at one time in the west wall near the south end of the vault, but it was sealed over with stacked stone at some point.”
City bosses have yet to decide their next steps with the vault so the hole leading to the vault has been covered.
“It is similar in construction to powder magazines of the same period but other theories have been pitched as well,” April further added.
“Until it can be explored in more detail, we can only speculate as to its function at this time.”
She said: “Our finds suggest that structures related to the 18th-century occupation of the site may still remain in an area that has not yet been investigated.”
In his lifetime, Cornwallis founded Halifax, implemented Canada’s first constitution, became governor of Gibraltar, and married the niece of Britain’s first Prime Minister, Robert Walpole.
However, his fame would be surpassed by his nephew, Charles Cornwallis, who surrendered to George Washington in the last battle on American soil in the War of Independence.