Great question — answering as the UphillTech team:
Bottom line: You can't really ensure your safety while hiking inside or near old mine fields. Such areas are best avoided if you value your legs... and what's attached to them. Old mines can be triggered by a variety of circumstances. They might have been designed for a specific weight trigger, but after decades of decay, you can't reasonably expect any mine to be operating within design specifications (and they often don't operate within specs even when they are brand new). Sometimes growing roots or shifting/tumbling rocks can even trigger them. Expansion/contraction of land substrates due to changing temperatures can also result in mine detonations. Any area with undetonated mines can...
Full answer by Amazon Dies In Darkness: https://outdoors.stackexchange.com/a/28757 (CC BY-SA 4.0).
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