Serene Hoh Xil Lake. [Photo/VCG]

In his vain attempt around the year of 1900 to reach the holy city of Lhasa, Swedish explorer Sven Hedin (1865–1952) crossed the Chiangtang Plateau, the northwest of the Qinghai-Tibet Plateau, where Hoh Xil is located.

According to his travelogue, the Chiangtang Plateau was an ethereal land, where his body was pushed to the limits and he "who lives for adventure" suffered hunger and cold, as well as nosebleed ... It was through his and several other explorers' writings that Hoh Xil and its vast surrounding areas began to be noticed by the world. Yet for more than half a century after Sven Hedin's visit, Hoh Xil had still hardly been elaborated in books on adventures.

Known as the "third pole" of the Earth due to its unique geographical location, the Qinghai-Tibet Plateau has a significant impact on climate change in Asia and the whole world. The international scientific community attached greater importance to the plateau in the 1960s and 1970s. Since most of the plateau is in China, the Chinese scientific community want to have more results that could guide and serve the national development. As the Qinghai-Tibet Plateau has a direct bearing on the sustainable development of China's economy and society, the study of it is of tremendous scientific value. From 1973 to 1992, the Chinese Academy of Sciences organized China's first comprehensive scientific expedition to the Qinghai-Tibet Plateau. By the end of the 1980s, most of the plateau had been explored, with the exception of Hoh Xil. In order to find the last piece of the puzzle, the expedition team organized by the Chinese Academy of Sciences and other institutions entered Hoh Xil from 1989 to 1990 to unveil its mystery.