The Mogao Caves are the reason to come to Dunhuang and one of the great sights of Asia. Carved into a 1.6-kilometre cliff face about 25 km southeast of town, 492 surviving caves contain over 45,000 square metres of murals and more than 2,000 painted clay sculptures, dating from the fourth to the fourteenth century. The art chronicles a thousand years of Buddhist iconography blending Indian, Central Asian and Chinese styles — flying apsaras, jataka tales painted like comic strips, serene Tang Buddhas, Yuan-dynasty Vajrayana mandalas — preserved by the dry desert air.
Visiting is now tightly controlled. Tickets must be reserved in advance (book online or through your hotel — they sell out in summer), and you watch two introductory films at the visitor centre about 15 km from the caves before being bussed out. On the cliff itself a guide takes a group of fifteen or so through eight or ten caves chosen on the day; you cannot pick. Photography is forbidden inside, torches are issued, and the visit takes about two hours. The art is so dense and the lighting so dim that one visit is enough to overwhelm; serious enthusiasts come back a second day with different cave assignments. Caves 16/17 (the Library Cave) and 96 (the 35-metre seated Buddha) are nearly always shown.