In the past years, found out in Kangdong area were lots of relics dating back to the New Stone Age, but not remains and relics dating back to the Old Stone Age.

Discovered in the said cave were 16 pieces of stone tools, more than 1,650 pieces of fossil animal bones and 280-odd pieces of spore and pollen fossils from the cultural layers of the Old Stone Age (fourth and fifth layers), five teeth of a Korean ancient and 40 earthenware pieces from the cultural layer of the New Stone Age (sixth layer) and 12 earthenware pieces from the cultural layer of the Bronze Age (seventh layer).

Through measurement of remains by means of electron spin resonance (ESR) and thermo-luminescent dating (TL) and research into kinds of stone tools and their materials and making methods, the group proved that the formation age of the cultural layers of the Old Stone Age is more than 36000-34000 years ago.

It also verified, with remains discovered in the cultural layer of the New Stone Age, that the progenitor of old Korean is based on the Neolithic man like neoanthropus in late Paleolithic age whose fossilized bones were discovered in Mt Sungri in Tokchon City, South Phyongan Province and in Ryonggok Cave in Sangwon County, North Hwanghae Province.

All the facts evidently show that Kangdong area, where the ancestral father of the Korean nation Tangun is entombed, is a time-honored place that men have lived from the Old Stone Age.

The newly-discovered relics are of weighty significance in making a scientific clarification of social relations and productive activities of the then people and the origin of the Korean nation.

The Archaeology Society of the DPRK and the Non-permanent Tangible Heritage Examination and Appraisal Committee examined the cave relics in Hyangmok-ri and registered it as a national treasure.