Viewing an online map in satellite mode, it’s the snowy line of the Himalayas that arrests the eye: there’s a sense of energy, almost of movement. Like a dazzling white wave, the world’s greatest mountain range seems to surge across the heart of Asia. To the southwest lie the scorching plains of India; to the north, an endless emptiness of arid steppe; while to the southeast, the mountains wheel around, tapering away into the land of Myanmar (Burma). To the east, subsidiary mountain ranges spill across the Tibetan Plateau and over into western China, apparently swirling, eddying and jostling one another as they go. The last big splashes on the map are the Qionglai and Qinling Mountains.