Relics of the Hoa Binh and Bac Son cultures date from 17,000 to 7,000 years ago, associated with the Flandrian Transgression. Relics are found in such caves as Nguom Boc (Hoa An), Nguom Cang (Trung Khanh), Hang Na Con (Nguyen Binh), Nguom Chieu (Quang Uyen), and on the terrace of the Binh Long river (Hoa An), as well as in some other caves outside the Geopark, such as Nguom Cang, Nguom Vai, Hang Than (Thong Nong district). Stone tools found of moderate size, manufactured from river and stream gravel using rudimentary flaked or simple blading techniques. Studies of occupation and settlement sites suggest:
– Although limestone valleys and caves were home to most of the inhabitants of this epoch, in the northeast mountainous areas hilly terrain and river terraces were also favoured for settlement.
– Preferred hunting and gathering areas were lowland and mountain river valleys, and forests.
Nguom Boc cave (Hoa An)
Nguom Boc cave monument is in the territory of Ban Nua commune, Hong Viet, Hoa An district (coordinate: 617256, 2511578); It is a national revolutionary historical site about 2km to the north of Hong Viet commune center. At this place on October 1950, President Ho Chi Minh generalized the Border Campaign. (Nguom Boc means Dry Cave in local language). In the famous Pu Luong – Sao Cai legend of Tay – Nung people, it was the first residence of the two aforementioned legendary figures in Cao Bang. The cave distributes in the western slope of Lam Son Mountain with a large dome-shaped cave mouth opening to the west and an area of about 300m2, divided into two large chambers. The first chamber is located and the second chamber has 2 stone pedestals which were built by cement and relatively big. These are the vestiges of machine pedestals of a military weapon workshop in the 1950s.
The relics include:
+ 3 rudimentary chopping tools, 1 Hoa Binh-style oval tool, 2 scraping and cutting tools, 2 grinding pestles, 3 material pebbles; all were processed from pebble stones in rivers and streams by simple flaking and chipping techniques. The tool shapes are typical of Paleolithic nuances. Nguom Boc collection does not contain Son Vi technical characteristics but processing in Hoa Binh style is still fuzzy.
Raw chopping tools
+ The presence of a sediment block which is more than 1 meter thick and densely containing stream shells suggests they were food remains of the prehistoric man living in a rainy period with the development of aquatic species. Based on C14 analysis of stream shells in the sediment (results: 7.420 +-95 yn and 6.820 +- 95 yn), archaeologists have predicted that the layer of archeological site dated back to about 10,000 years ago(there are still approximately 10m3 of sediment containing stream shells and tools, distributing along both sides near the cave entrance).
Based on the overall research on archaeological relics, colors and compositions of sediment and fossilization levels, archaeologists assumed Nguom Boc is a resident relic of the primitive people living at the beginning of the Holocene period about 10,000 years ago, equivalent to the period of early Hoa Binh culture.
Nguom Cang cave (Trung Khanh)
Nguom Cang cave monument is located in Ban Gioc, Dam Thuy, Trung Khanh district. Coordinate: 675737, 2528391; It has a dome-shaped entrance with approximately 15-20m width, ~10m height, many stalactites hanging, facing the north. There is a karst valley in front of the cave. The ancient karst cave floor is about 3m above the field surface. The cave is quite wide with an area of about 300m2; a small niche penetrates into the cave in the southern part.
Archaeologists have surveyed (May 2001) and preliminary discovered 23 stone relics of the primitive people. In particular, 7 templates were found on the surface and 16 artifacts were in the cultural layer, including rudimentary chopping and hitting tool (horizontal blade edge), flake tools, flaking and hitting stone, flakes, pebbles with flaking traces.
Cutting, scraping tools, chipping stone, grinding pestle in Nguom Xe, Nguom Gang, Ban Gioc village, Dam Thuy district, Cao Bang; Age: Stone Age about 10,000 years ago; time of detection: October 17, 2003 (Cao Bang Museum)
Most of the relics were processed from pebbles. It is likely that Nguom Cang residents found pebble source in Quay Son River to make tools. Flaking and chipping techniques were simple, direct and limited on one side and on the edge of pebbles. Tools have an ancient look; formativity in tool shaping technique is low; and forms of tool typical of the Paleolithic traditional culture are not diverse. There is no grinding stone and pottery. These remains show gathering had a particularly important position in the methods of searching for food sources of the primitive people . Based on processing techniques, types of relics found and sedimentation level of the cultural stratum, archaeologists initially assumed Nguom Cang is the residence monument of Stone Age people in the early Neolithic period.
Nguom Cang cave (Thong Nong)
Nguom Cang cave is located in Vi Quang commune, Thong Nong district (outside the Geopark) (Nguom Cang means Gibbon cave). Nguom Cang is essentially a stone roof distributing over the steep slope of a limestone mountain – limestone slope and wall are vestiges of NW-SE tectonic fault. The height the wall foot up to the cave entrance is about 50 meters; there is a tectonic valley in front of the cave entrance and Thang Lat stream along the valley. Nguom Cang monuments include:
+ Monuments (3 types)
– Fire monument: a greyish white ash layer with uneven thickness from 2cm to 4cm has been discovered. In the coal ash was burnt shells and some broken animal bones.
– Animal bone, tooth monuments are identified as of deer, pig, goat, monkey, bamboo rat, chicken, bird, porcupine etc. Notably there is a piece of pig jaw with burn marks, indicating they are the remains of the ancient food. Most animal bones and teeth have not fossilized.
– Mollusk shell monument: more than 30 stream shells with traces of cut penultimate whorl and many crab pincers.
+ Stone relics:
– Group I: the group of traditional tools with significant amount: 41.19%, including spike tools, horizontal edge tools, vertical edge tools etc. This relic group is classified as typical tool group of Son Vi culture of the late Paleolithic period. However, when examining, archaeologists also found differences between the traditional tool group in Nguom Cang (Thong Nong) and Son Vi tools in Lao Cai, Phu Tho, Yen Bai, or in the Northwest area. Analysis of processing technique also found differences between the traditional tool groups in Nguom Cang with Son Vi tools, typically in processing types of vertical edge chopping tools, pebble quarter tools etc.
Flakes, whetstone, grinding pestle, chopping tools discovered in Nguom Cang in the early Paleolithic period
– Group II: The group of tools of Hoa Binh – Bac Son style takes up of a large proportion in Nguom Cang: 16.05%. They represent the rich and stable Hoa Binh techniques in a number of specific forms, including oval tools, disc-shaped tools, short axes made from unbroken or broken pebbles and mainly having a side flaked by radial flaking technique – Sumatralith technique. Statistics show the majority of Hoa Binh featured tools in Nguom Cang is oval axes (Sumatralith) and short axes. Notably in Nguom Cang collection is “Bac Son trace” relic. The appearance of this relic is likely to be the hallmark of the cultural communication between Hoa Binh inhabitants and Bac Son culture inhabitants. A rather common technique in Nguom Cang is the flaking technique with limitations in pebble edges on one side and in one direction – creating rudimentary chopping tools or spikes. This is a fairly old technique, popular from the Paleolithic and typical of Son Vi culture – a late Paleolithic culture in our country.
Another typical flaking and chipping technique in Nguom Cang is radial flaking and creating forms of Sumatralith tools with oval, dish shape, short axes etc.
Whetstone tool (Nguom Cang cave, Thong Nong)
Chopping tool (Nguom Cang cave, Thong Nong)
A notable technique is grinding technique in Nguom Cang relics – this is a revolutionary factor in the primitive techniques. It completely changed the appearance of flaking and chipping tools which were familiar in millions of years and improved the productivity of the tools.
+ Production methods: Researches on archaeological sites show hunter-gatherer mode is a remarkable feature of daily life of Nguom Cang residents. Whetstones and grinding pestles are vivid evidence of processing food from the flowers, fruits, bulbs and roots of ancient residents here. A large number of spring snail shells found with traces of cut penultimate whorl prove they are an important part of the ancient human food supply. Nguom Cang residents had a rather broad relationship with contemporary residents instead of living in isolation. Studies on stoneware here show that the oval tools, short axes in Nguom Cang are quite similar to the tools of the same type in Ha Giang, Tuyen Quang.
+ Determination of age: Overall research on monuments and relics collected in Nguom Cang cave indicates it is a monument of the early stage of Hoa Binh – Bac Son culture, early Neolithic culture dating back to approximately 8,000-9,000 years ago.