Photo Credit: Police of the Slovak Republic
A magnet fisher along the Danube in Slovakia pulled up far more than scrap metal: an unexploded World War II-era British anti-ship mine weighing more than 1,500 pounds.
The mine surfaced near Virt, close to the Hungarian border, where intense heat had pushed the river to unusually low levels and exposed material that had long remained hidden underwater.
Here’s what to know
Slovakia had never before defused such a large unexploded mine of this type, Popular Science reported. Archaeologists said it was likely left from Royal Air Force operations on the Danube between April and October 1944 that were meant to disrupt Nazi transport.
Those raids sharply reduced shipping on the river, with Danube traffic falling by an estimated 60% to 70% and dozens of vessels sunk. The missions, known within the RAF as “gardening” operations, involved 18 attacks and 1,382 mines, and the disruption helped open the way for Soviet forces advancing westward.
Low water on the Danube has also revealed other wartime relics in the region, including WWII-era Nazi motorcycles and shipwrecks in Serbia and Hungary. This find was different because the object pulled from the river still posed an immediate threat.
That threat reaches well beyond archaeology. When extreme heat and drought shrink major rivers, they can expose hidden explosives, disrupt shipping routes, and strain water supplies for nearby communities. Worsening extreme weather disasters undermine public safety, increase heat-related and environmental health risks, and create economic instability for regions that rely on transport, tourism, agriculture, and dependable access to water.
More background
Not all wartime explosives in the Danube were recovered after WWII, which is why some remained in the river for decades. As currents shifted sediment over time, the devices were concealed until lower water made them visible again or easier to snag.
Europe’s intense heat waves are not only creating the immediate dangers tied to high temperatures, but also uncovering older hazards that can still injure or kill people more than 80 years later.
Nearby residents may face new restrictions along riverbanks, heightened safety concerns for fishers and boaters, and potential disruptions to river traffic. The Danube is one of Europe’s most important waterways, so even localized threats can ripple outward through commerce and travel.
What’s being done?
In Slovakia, the discovery was handled as a major public safety operation. Police, the Fire and Rescue Corps, and explosives specialists from Bratislava’s Institute of Criminology and Expertise coordinated the removal so that the mine could be secured without being detonated.
Once it was brought out of the Danube, the mine was loaded onto a specially adapted fire truck with a sand bed to cushion and stabilize it during the trip. Officials then transported it to an isolated, unpopulated site.
There, crews excavated a pit about 16 feet deep, placed the mine inside, covered it, and destroyed it with a controlled remote blast. That process eliminated the threat while minimizing the risk to nearby communities.
Officials warned residents not to go looking for similar objects on their own. Although RAF crews once gave these mine-dropping operations the mild name “gardening,” the blast in Slovakia was a reminder that the weapons left behind can still be deadly.
Get TCD’s free newsletters for easy tips, smart advice, and a chance to earn $5,000 toward home upgrades. To see more stories like this one, change your Google preferences here.
