A 100-kilometre ridge of bare red sandstone hills running northeast from Turpan, marking the northern rim of the Turpan Depression. In the afternoon sun the eroded gullies and ridges genuinely look like flames; the official Turpan tourist site has the predictable giant thermometer and Journey to the West statues.
The mountains hide most of the Silk Road's surviving Buddhist cave sites — Bezeklik, Toyok, and the rarely visited grottoes at Shengjinkou — and the deep valley of the Murtuk River, an unlikely strip of green winding between the red cliffs. Best visited as part of a Bezeklik or Gaochang itinerary.