Anyone underwriting property in California has spent the past couple of years staring at wildfire risk in granular detail: fire behavior, fuel loads, wildland-urban interface exposure, all of it. It's a hard peril, and the US market knows it well.
Watching this summer's European wildfire season is a reminder that it can get harder. Bury a few million tons of unexploded World War I and II ordnance under the same ground that's now burning, and fire crews end up fighting two hazards at once.
Wildfires driven by drought and record heat have swept across France, Belgium, Germany and the Netherlands this year, and in several places they've triggered the munitions buried beneath the land they've burned. In the French village of Le Porge, near Bordeaux, a wildfire uncovered roughly 400 shells and pieces of ammunition, mostly German and French mortar rounds and anti-tank shells, according to French officials; one resident told regional media that a piece of the recovered ordnance had gone straight through a house.
In eastern Belgium's Liège province, home to the WWII battlefields of the High Fens, the regional governor confirmed sporadic detonations during recent fires, with emergency crews adapting their response around buried munitions. A Dutch bomb-disposal unit was sent to check a forest near a former WWII combat site in Limburg as flames closed in.
Old ordnance turning up in Europe is nothing new. Belgium's Explosive Ordnance Disposal and Destruction Service handles more than 3,000 call-outs a year, clearing 200 to 250 tonnes of old munitions annually, and in Ypres, the WWI battlefield town, farmers have a name for the debris that turns up every time they till a field: the "iron harvest." What's new is fire doing the digging. Jonas Tepe, a regional government spokesperson in North Rhine-Westphalia,
Germany, has noted that unexploded ordnance becomes especially dangerous around wildfires because heat alone, without direct flame contact, can be enough to set it off. Dr Sarah Njeri, a peace and conflict researcher at SOAS, University of London who studies the environmental legacy of landmines, frames it as Europe's "climatic luck" running out. Decades of relatively stable weather kept buried contamination inert. That stability is gone.
The scale explains why this keeps happening. The EU's satellite-based European Forest Fire Information System had already recorded upwards of 500,000 hectares burned across the bloc by early August 2026, ahead of the same point in 2025, itself the worst year on record. More burned ground means more exposed ground, and in large parts of Western Europe, exposed ground has an unusually high chance of holding something that goes bang.
The raw material for a smaller version of the same story sits on American soil too. The Department of Defense currently suspects or acknowledges military munitions contamination on roughly 15 million acres of former training ranges and testing sites nationwide, known as Formerly Used Defense Sites, with cleanup costs estimated at $8 billion to $35 billion. A number of them sit in California, currently the most wildfire-scrutinized property market in the country: the former Fort Ord training grounds in Monterey County, the Victorville Precision Bombing Range in San Bernardino County, and the Trabuco Bombing Range in Orange County among them. Most of that land is now grazing pasture, housing, or open space rather than active training ground, which is roughly the profile of the European sites now burning. Old military land and modern wildfire risk overlap here too. Europe is just further along in finding out what that means.
There's a market-level reason to pay attention beyond the novelty value. Wildfire has already stopped behaving like the secondary peril it was long modeled as, on both sides of the Atlantic, and reinsurers pricing European property exposure are largely the same reinsurers pricing California and Colorado exposure. A worse-than-usual European fire season, complicated further by ordnance-driven evacuations and detonations, feeds into the same global catastrophe capital pool US carriers draw on for their own wildfire-exposed books. It's one more input in a year when wildfire risk is already being priced at the neighborhood level rather than treated as background noise.
A US property owner shouldn't expect to unearth a Wehrmacht mortar shell in the backyard. Most of America's legacy ordnance sites are well documented, well outside populated areas, or already managed under long-running federal cleanup programs. Watching European crews handle fire and buried explosives in the same shift is still a useful reminder of how many hazards can stack on one piece of ground, and how a warming climate has a habit of finding all of them at once.
