The Vietnam War
The Vietnamese consider themselves a nation of proud and victorious soldiers. An example of their cunning and resourcefulness is the Cu Chi tunnels - a 350km-long labyrinth of tunnels complete with underground kitchens, schools, hospitals and emergency escape routes. The tunnels provided a refuge for 3000 villagers, and despite being bombed, gassed, flooded and poisoned, they managed to evade the Americans for 8 years.
A bat in the claustrophobic darkness of the Cu Chi tunnels

A sketch of the tunnels showing an emergency escape route into the river

An abandoned tank in a southern town