Minefields

Minefields are considered a defensive or harassing weapon, used to slow the enemy down, to help deny certain terrain to the enemy, to focus enemy movement into kill zones, or to reduce morale by randomly attacking material and personnel.(...) The extents of minefields are often marked with warning signs and cloth tape, to prevent friendly troops and non-combatants from entering them. Of course, sometimes terrain can be denied using dummy minefields.(...) Some minefields are specifically booby-trapped to make clearing them more dangerous. Mixed anti-personnel and anti-tank minefields, anti-personnel mines under anti-tank mines, and fuses separated from mines have all been used for this purpose.

A land mine can be triggered by a number of things including pressure, movement, sound, magnetism and vibration. Anti-personnel mines commonly use the pressure of a person's foot as a trigger, but tripwires are also frequently employed.(...) Many mines combine the main trigger with a touch or tilt trigger to prevent enemy engineers from defusing it. Land mine designs tend to use as little metal as possible to make searching with a metal detector more difficult; land mines made mostly of plastic have the added advantage of being very inexpensive.

Removal of land mines carries certain risks and can be slow and costly;(...) Demining is the process of removing land mines or naval mines from an area.(...) Deminers may be issued with personal protective equipment (PPE) such as helmets, visors, armoured gloves, vests and boots, in an attempt to protect them if a mine is set off by accident. Related technologies that have been developed to improve safety include large, pillow-like pads strapped to the bottoms of shoes that distribute weight and dull the impact of footsteps, as very slight disturbances of the ground can tip off old, unstable, or intentionally sensitive mine triggers.

From Wikipedia, articles: Land mine; Demining