Archaeologists investigating prehistoric sites of the New Stone Ageon the Tanggula Range on the Qinghai-Tibet Plateau believe people at that time might have roamed some 5,000 meters above sea level.
The 13 prehistoric sites were discovered during the exploration of the Tibetan section of the Qinghai-Tibet railway, which is under construction.
Distributed on the Tanggula Range, the sites were all at an altitude of between 4,700 and 4,900 meters above sea level, said Gengdui, a research fellow with the Tibet Museum.
"From those sites of 4,900 meters high, we can draw the conclusion that ancient people living on the Qinghai-Tibet Plateaucould move about in an area above 5,000 meters," said he.
"Located along the banks of the Buqu River snaking in the Tanggula Range, most of the sites are shelters from the wind, close to water and convenient for communications, thus providing suitable living conditions," he said.
Some of the instruments discovered at the sites are made of quality stone and of a high degree of technical skill.
"Most of the instruments have multiple uses, a main characteristic of instruments unearthed in the prehistoric cultural sites in the Eurasia Continent," he said.
"Such instruments have also been discovered at other places in Tibet. So we consider it forceful evidence for the existence of ancient humans on the Qinghai-Tibet Plateau," he added.