The Vinh Moc tunnels are situated 19 km north of the Ben Hai river. Faced with incessant bombing by US and ARVN forces, in what was termed a free fire zone, the villagers at Vinh Moc were faced with three options. One was to leave their homes and livelihood, two was to stay in their homes and probably be killed, or three was to start digging. They took the third option and embarked on an excavation project, taking 18 months to complete, that would eventually relocate the entire village underground. Similar tunnels were attempted at nearby villages, who were also in the free fire zone, however they were not of the same standard. At Vinh Quang, as a result of bombing by US forces, the tunnels collapsed, killing all inside.