The Roof of the World or Top of the World is a metaphoric epithet or phrase used to describe some of the highest regions in the world. The term usually refers to all or part of High-mountain Asia, the continent's mountainous interior, including the Pamirs, the Himalayas, the Tibetan Plateau, the Hindu Kush, the Tian Shan, the country of Nepal, and the Altai Mountains.
The British explorer John Wood, writing in 1838, described Bam-i-Duniah (Roof of the World) as a "native expression" (presumably Wakhi), and it was generally used for the Pamirs in Victorian times: In 1876, another British traveler, Sir Thomas Edward Gordon, employed it as the title of a book and wrote in Chapter IX:
Older encyclopedias also used "Roof of the World" to describe the Pamirs:
With the awakening of public interest in Tibet, the Pamirs, "since 1875 ... probably the best explored region in High Asia", went out of the limelight and the description "Roof of the World" has been increasingly applied to Tibet and the Tibetan Plateau, and occasionally, especially in French (), even to Mount Everest, but the traditional use is still alive.
Tibet is commonly known as Roof of the world, click for detail about Tibet