WW2? We're still finding explosives from WW1 in Belgium

True that. I used to work in the Netherlands, and sometimes it seemed like every other week the rail network was disrupted by a newly-discovered unexploded bomb, left over from the plastering the Allied air forces gave the Dutch railways.

Just few months ago, a 1,000-pound WWII bomb was found in Hong Kong. The city had been a battlefield between Japanese and Allied forces.

https://hongkongfp.com/2025/09/19/hong-kong-to-evacuate-6000...

Indeed. With landmines from 90's at least general areas are known, there's signage and if you're not being stupid by venturing way past signage it's all really safe to be around.