Medieval cannonballs and WWI bomb discovered under construction site

Renovations on government buildings in the coastal Belgian town of Nieuwpoort are currently on hold after surveyors discovered an impressive archaeological trove: dozens of carefully crafted stone cannonballs dating as far back as the 14th century. However, the medieval ammunition backstock wasn’t the only weaponry buried roughly 70 miles west of Brussels. According to city officials, experts also excavated an unexploded artillery shell from World War I.

“What has been exposed here in recent weeks proves that Nieuwpoort is a city where history is literally everywhere. Even a few meters under our feet,” Nieuwpoort Mayor Kris Vandecasteele said in a statement.

Investigations into the small plot of land began in February, after preliminary test digs indicated promising archaeological relics in the area. Since then, excavations have yielded numerous stone cannonballs near the site of what was once the city’s southern fortification wall. Researchers say that the carefully assembled stockpile and its location suggest it was an intentional store of ammunition dedicated to the town’s defense. This is further supported by the dig’s location near the city’s historic Stadshalle civic center and belfry, but this is not a definitive confirmation.

Stone cannonballs like those uncovered in Nieuwpoort represent an important transitional phase in medieval military technology. Popular across Europe between roughly 1350 and 1600, the ballistics could be fired from not only mechanical catapults and trebuchets, but explosive cannons. As Arkeonews highlights, the variations in cannonball size also suggest a mixed arsenal stocked for multiple types of weapons.

One additional discovery provides a poetic—if eerie—symbol of Nieuwpoort’s military and technological history. In a more recent soil layer, archaeologists also located an unexploded artillery shell that crashed into the ground during World War I. While Belgium’s explosive ordinance team safely removed the potentially volatile artifact, the shell serves as a reminder of the city’s longstanding strategic importance, due to its location on the English Channel. Nieuwpoort functioned as a front-line European city during WWI, and experienced widespread damage as a result of its location.

“What we find here exceeds our expectations: from medieval building structures and an exceptional depot of cannonballs to military relics that point to our past as a front city,” said Nieuwpoort Heritage Alderman Ann Gheeraert. “These excavations confirm that every construction phase in Nieuwpoort is also a journey of discovery into our own history, a past that has not yet revealed all its secrets.”

 

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