Detail from Stein's map showing area on western edge of the Takla Makan from Yarkand to Kashgar to Aksu - and crossing the desert is the Khotan River - The Tibetan fort at Mazar-tagh is next to the river toward the south. The ruins at Kelpin are west of Aksu. Maral-bashi is near the Kashgar and Yarkand Rivers - Stein went there in hopes of moveing directly across the desert east to the Khotan river but was forced to turn back by high dunes.