In more than one sense, the Stone Age has never ended in Vietnam, because the country's infatuation with rocks can be considered a cultural heritage.
A typical earthen-walled house built by ethnic minorities surrounded by stone fences in the Dong Van Plateau of the northern highland province of Ha Giang
Testament to this are several centuries-old villages that have been established on stone, telling vibrant stories of creativity and adapting to the local environment.
In the northern mountainous province of Ha Giang, an endless succession of rocks seems to make up the homeland of the Meo and, H'Mong people.
The rocks are everywhere, in the terrace fields and at home, where mortars, beds and stables are made of stone. One of the most picturesque aspects of the local landscape are the earthen-walled houses built by the ethnic minorities surrounded by stone fences.
For hundreds of years, these residents have interacted closely with their natural environment to make a living. They lift stones to sow corn and rice, and build cattle sheds on cliffs. Stones are also used to lay the foundation of a house and to pave roads.
Rocks are the centerpiece of the distinct architecture found in the area.
The stony topography has also forced residents to come up with a unique farming system, whereby crops last up to one year, and small ploughshares can be fit into stone slots to turn over the small areas of soil underneath.
To grow maize, residents have to carry baskets of soil up the rugged mountain and place it between the hollows on the rocky terrain before sowing the seeds.
In the Red River Delta, besides the 350 ancient houses built in the 17th century, the yellow ochre of laterite stone walls makes the Mong Phu village stand out among the nine ancient villages in Hanoi's Duong Lam Commune.
Unlike the stone from Thach That, Quoc Oai, or Son Dong districts in Hanoi, Duong Lam's rough laterite stone are unprocessed and can be used as bricks by merely stacking them up to form walls.
Mong Phu's deserted paths, covered by closed wooden gates, which connect laterite walls spotted with green moss, transport visitors to bygone eras like a smoothly functioning time machine.
In the central province of Quang Nam, for over 500 years, in life and death, stone has been integral to the people of Tien Phuoc Village. They may not have had stone that is as beautiful as the laterite stone in Mong Phu or as hard as the rock in Ha Giang, but the culture of this land has been enriched by the ways in which stone has been used in daily life.
Located on the mountain, Tien Phuoc has many precious kinds of wood that have been used to make beautiful houses since the 15th century when King Le Thanh Tong called on people to head to the south and establish new villages.
Such beautiful houses needed reliable fences, and the obvious choice of material was stone, available in plenty around the area. So stones of different shapes and sizes were piled up around the beautiful houses, each fence with its distinct character.
For the gate, natural flat stones were taken, looking like man-made bricks. At each side of the gate stood two parallel columns of stone 1.5m high with 0.4m gaps in between them. These gaps were filled with soil and then planted with a kind of wild tea with small round leaves and a beautiful shape. The plants sent out roots into the slits between rocks, compacting the soil and sustaining the high walls
Stones, stones everywhere: Ethnic minority residents of Dong Van Plateau have learnt to use their surroundings to their advantage
There are houses that are stand several dozen meters higher than the street. To get to the house, stone steps pave the way. These steps are also a work of art, with stones of different shapes and sizes bound together with a mixture of lime and a dao (a plastic substance derived the cooked dried buffalo skin) or molasses.
On bright moonlit nights, boys and girls in the village met on beautiful stone lanes, singing to one another. Stone lanes became "natural stages" for people to show off their talent in singing and looking for life partners.
A folksong in Tien Phuoc says: "Sitting on a stone gateway can release sadness."
Before the advent of cement, it was common practice for the dead to be buried in stone tombs.
Square, rectangular, or oval, the tombs were surrounded by stone ramparts as well. Unlike tombs in other areas, those at Tien Phuoc have stood intact for 500 years.
As recently as 50 years ago, stone fences several meters high were built to protect people, cattle and crops from attacks by wild boars and tigers that would approach villages on dark nights.
People even used ham heo (wild boar tunnels made of stone) to trap wild boar. Ham heo have two stonewalls of about one meter high each that a wild boar is chased into.
The opening of the road, which can be up to a kilometer long, can be several meters wide, but narrows gradually before the tunnel becomes about 3-4 meters deep.
The road slopes by about 45 degrees, so it is easy for the wild boar to run down, yet impossible to go up.
At night, people burned torches and beat the gong to chase the wild boars into the road between two cliffs and the animals would end up in the tunnels.