The history of Qinghai-Tibet Plateau is very interesting. The Qinghai-Tibet plateau used to be a part of the ancient sea, but became land when the waters receded during the late Eocene Epoch about 10 million years ago. The rise of the Himalayas, and behind the towering mountain ranges the Tibetan Plateau, was one of the greatest events in world geological history.
Although it this occurred somewhat during the Cenozoic Era, the origins cam be traced back the Mesozoic and Paleozoic eras. According to the continental drift theory, the Indian continental plate drifted northward and came into violent collision with the Eurasian Plate. As the land was forced upwards, the ancient seas drained off to the east and west to expose what became the Qinghai-Tibet Plateau.
The Himalayas have been rising ceaselessly. The average elevation was about 2,000-2,500 meters, with a few peaks rising to 3,000 meters or so during the Pliocene Era about 10 million years ago. At this time the Qinghai-Tibet Plateau even had a period of tropical and semi-tropical climate. Until three million years ago, the Himalayas never rose above a height of 4,500-5,000 meters.
Subsequently, because the mountains continuously grew and continued to rise towards the sky, forming the lofty mountain body barrier of the Himalayas that we know today, the warm and wet monsoon air from Indian Ocean could no longer pass through and that drastically altered the natural environment of the southern and northern slopes of mountain ranges. Great changes took place in terms of animal and plant life and the climate. While the late Ice Age and Middle Ice Age climatic patterns emerged frequently, the Plateau climate developed continuously in the direction of dry and cold weather.
The Tibet Plateau has a human-inhabited history of at least 50,000 years. Stone implements of the late Paleolithic Era were found in the eastern, southern and northern parts of the plateau; the ruins of the Neolithic Age were even richer, like the famous Karub ruins in Qamdo, Lhasa Gongqu Village ruins and so on. The Tibetan ethnic group are the descendants of those ancient people, who lived in Qinghai-Tibet Plateau during the Neolithic Age.
Now, the Qinghai-Tibet Plateau becomes more famous world widely for the world's highest railway, Qinghai-Tibet Railway, through which travelers can enjoy an amazing Tibet train tour to Lhasa from Beijing, Shanghai, Chengdu, Xining and other cities of China.