Here is the biggest, best-preserved, and most significant site of Buddhist statuary and frescoes in all of China -- and the best-curated site, too. A guide is compulsory, as is leaving your camera (no charge) at the gate. Generally the guides, who all have bachelor's degrees, are excellent, sometimes going well beyond the script. Tours, which depart every few minutes and are limited to about 20 people, usually take 2 hours and cover 10 of the 30 caves that are open to the public; Caves 16, 17, 96 and 148 are included on all tours. Tours in the afternoon are less crowded, and you may get a guide to yourself. Or come right as the caves open in the morning, before the tour groups arrive. Although guides have powerful flashlights, it's worth bringing your own to see the murals in some of the darker caves.
Before you reach the grottoes you'll see the Dunhuang Exhibition Centre, which includes a copy of the one of the earliest grottoes, Cave 275, dating from the short-lived 5th-century Northern Liang dynasty, including a Jataka (moral story) from one of the historical Buddha's previous lives. He is depicted as a Kushan king, allowing an attendant to cut the flesh from his leg as ransom for a dove that sits in his palm. Jataka were popular in the early caves, gradually being displaced by stories from the Mahayanist sutras in later caves as the influence of the "Pure Land Sect" of Chinese Buddhism grew. The subject matter of these Jataka was frequently gory. Cave 285, for example, tells the tale of 500 rebels who fought against the corrupt King Prasenajit and had their eyes gouged out and were banished to the wilderness before the gods took pity on them and allowed them to be tonsured as monks, their sight restored by the Buddha. Upstairs is a somewhat out-of-place exhibition of Tibetan bronze statues, both complete and beheaded, that were rescued from Red Guards by the canny curator.
All together, there are 492 caves, of which you will see a mere 10 on the 2-hour tour. Your first stop on the tour will be Caves 16 and 17 (the Library Cave). The cave was sealed off sometime after 998 (the year of the last dated manuscript), perhaps out of fear of the spread of Islam -- the Buddhist kingdom of Khotan was captured and sacked in 1006. In 1900, the cave was rediscovered by Wang Daoshi (Abbot Wang), the self-appointed guardian of the caves. First among the villains was archaeologist Aurel Stein, a Hungarian who obtained British citizenship (and later a knighthood), and who arrived during the winter of 1907. The Chinese commentary is only slightly more damning than the English translation, accusing Stein of "purchasing by deceit" over 7,000 complete manuscripts and silk paintings from the "ignorant" Abbott Wang for a paltry £130. Next came young French Sinologist Paul Pelliot, whose mastery of Chinese gave him a selectivity his predecessor lacked -- Stein returned to London with over 1,000 copies of the Lotus Sutra. Pelliot obtained thousands of documents for even less -- only £90! The Chinese save their greatest condemnation for Langdon Warner, who removed 12 murals (Cave 323) and a statue (Cave 328). Warner justified his theft as a way of avoiding the "renovations" funded by Abbot Wang. A map illustrates how the contents are spread around the world.
Curators, fearing that increased tourist activity is damaging the coloration of the frescoes, are closing some caves to the public. Some caves, considered of particular interest and import (such as Caves 275 and 285, detailed above), can be visited for an additional fee of ¥200 per cave per person. The caves depicting acts of love-making, much touted in other guidebooks, are generally off-limits. Remarkable early caves (usually open) include Cave 259, commissioned during the Northern Wei (A.D. 386-535); and Cave 428, where an early incarnation of the historical Buddha sacrifices himself to feed a tigress and her cubs. It's also worth asking to see Cave 249, which dates from the Western Wei; the cave's small size allows in enough daylight to see the exquisite lapis lazuli artwork on the ceiling. Later caves, such as Cave 96, which houses a 36m (116-ft.) Buddha, and Cave 148, which contains a serene 17m (56-ft.) Sleeping Buddha, indicate that artisans from the Tang court found their way to Mogao. Some lower caves were affected by floodwaters from the Daquan River, and sunlight has caused lead-based pigments to turn black, but the overall state of preservation is incredible. Caves are grouped roughly by period, and it is intriguing to view the steady transformation of facial features from Greco-Indian to plumper, more feminine Chinese features.