The Trans-Himalayan chain of Murtagh (or Karakoram), which is lost in the Tibetan uplands, passing to the north of the sources of the Indus.
The Murtagh (Snowy Mountain), the Karakoram (Black Mountain), and the Changchenmo are the most famous of these passes.
On the east the Pamir highlands are fenced off from the East Turkestan lowlands by the double border-ridge of Sarik-kol (the Sarik-kol range and the Murtagh or Kashgar range), which has its eastern foot down in the Tarim basin (4000-4500 ft.) and its western up on the Pamirs at 10,500 to 13,000 ft.
The general result of their investigations has been to prove that the o f India, Murtagh range, as it trends south-eastwards and finally forms a continuous mountain barrier together with the Karakoram, is the true water-divide west of the Tibetan plateau.
But we may follow Godwin-Austen in accepting the main chain of the Murtagh as merging into the central mountain system of the Tibetan Chang, its axis being defined and divided by the transverse stream of the Shyok at its westward bend, whilst the Karakoram range, in which the Shyok rises, is a subsidiary northern branch.
The Murtagh chain, which holds within its grasp the mightiest system of glaciers in the world, forms a junction with the Sarikol at the head of the Taghdumbash, where also another great system (that of the Hindu Kush) has its eastern roots.
Chief amongst them are the glaciers which have formed on the southern slopes of the Murtagh mountains below the group of gigantic peaks dominated by Mount Godwin-Austen (28,250 ft.
From the Dorah eastwards the crest of the Hindu Kush again becomes the boundary till it effects a junction with the Murtagh and Sarikol ranges, which shut off China from Russia and India.
The axis, or backbone, of Pamir formation is the great meridional mountain chain of Sarikol - the ancient Taurus of tradition and history - on which stands the highest peak north of the Himalaya, the Murtagh Ata (25,000 ft.).