Vietnam's Archaeological Academy and the Ha Giang Provincial Museum have excavated the Khuoi Nang cave and discovered vestiges of primitive civilizations that date back between 4,000 and 7,000 years.
Associate professor and PhD Trinh Nang Chung, who headed the dig team, said that they have uncovered two cultural layers reflecting two distinct periods of development.
Among the most fascinating finds was a pair of tombs constructed for an adult and child.
The remains of both bodies were discovered among a carefully constructed pile of stones.
According to local archaeologists, a formalized prehistoric burial site is considered a rare find in Vietnam.
The method of interment is believed to have derived from the belief that people are born from stone and that their spirits return to them after they pass.
Hundreds of stone-tools (knives, axes and mattocks) were also discovered at the site.