'Highly unusual' cannonball cache found at construction site in coastal city may be world's first

The discovery was made ahead of construction of an administrative center in Nieuwpoort, the city said in a recent press release.

In a translated statement, the city said the research "has already yielded highly valuable finds that may shed more light on an important chapter of Nieuwpoort's history."

Images from the excavation show dozens of stone cannonballs piled together, as well as exposed brickwork and soil layers that shed light on the city's medieval past.

Around 450 cannonballs were found in total. 

They date between 1350 and 1600 A.D. - and were likely fired from trebuchets or catapults.

"Their high degree of standardization and quality finishing suggests they were more likely intended for firearms," the city noted.

"Notably, the variation in sizes points to a highly diverse arsenal."

"The proximity of the site to the City Hall and its belfry, which has stood there since the 13th century, makes these findings particularly significant," officials said.

"It is still too early to draw definitive conclusions about the precise function and dating of these structures. Further analysis of the finds and additional dating efforts are expected to provide more."

Alexander Doucet, a fieldwork coordinator at the archaeological firm Group Van Vooren, told Fox News Digital that archaeologists have wrapped up excavation as of early April.

Archaeologists plan to spend up to two years analyzing the data and samples before compiling their findings into a final report.

Doucet called the discovery "highly unusual" - especially because the large cache was found in one location.

While the reason they were placed there is still a mystery, Doucet said the cannonballs may have been discarded into a cellar that needed to be filled.

"For now, the archaeologists have taken the cannonballs with them for further examination," he said.

"After this is completed, the owner of the cannonballs, the city of Nieuwpoort, can decide what to do with them. The archaeologists are going to make recommendations that the balls be displayed as a whole."