India, Nov. 1 -- The ancient river

The Indus river, fed by glaciers on the northern slopes of Mount Kailash, flows across the Byang-thang, the northern part of the Tibetan Plateau, before entering the Indian Changthang in south-eastern Ladakh. The river is a geologic antecedent to the Himalayas-its course predates the mountains' rise and has held that course ever since.

Over fifty million years, the river has cut deep gorges, and downstream, on its fertile alluvial plains, it sustained the Harappan civilisation for two thousand years until climate change and the river's shifting course dismantled it some three thousand years ago.

Across these immensities of time, humanity appears as a brief flicker-civilisations rising and vanishing li...