Archaeologists have discovered prehistoric sites dating back 20,000 years in Bao Thang district of the northern mountainous province of Lao Cai, said Associate Professor Dr. Trinh Nang Chung from the Viet Nam Institute of Archaeology on August 20.
The sites are in Khu Den and Ngoi Bat in Gia Phu commune, Soi Gia in Xuan Quang commune, and Ngoi Nhu in Son Ha commune.
In areas covering about 20,000 square metres, hundreds of stone artefacts belonging to several prehistoric eras have been unearthed.
The oldest items are working tools made from pebbles found in rivers and springs and dating back 20,000 years.
They also include stone axes and disk-shaped tools dating back to Hoa Binh culture in the New Stone Age about 8,000-9,000 years ago. Four-millennium-old polished axes were also found.
According to Chung, Ngoi Nhu was an uninterrupted residence of prehistoric people in Lao Cai and perhaps a large metal centre in the time of Hung Kings (2879-258 BC).
The excavation is still underway.