Yunlin Grottos lie 70 kilometers to the south of Anxi County, 180 kilometers to the east of Dunhuang.
The Yunlin Grottos are chiseled in the cliffs on both the east and west sides of the Yulin River. The east cliff has 30 grottos and the west has 11, with a distance of more than 100 meters between them. It used to be called Ten-Thousand Buddha Gorge. The grottos began to be chiseled and sculpted during the Northern Wei Dynasty (386-534), and was enlarged in the later dynasties such as the Tang (618-907), Five Dynasties (907-960), Song (960-1279), the Western Xia (1038-1227), Yuan (1271-1368) and so on. There are more than 1,000 square meters of frescoes, and more than 100 colored sculptures extant there.
The grottos in different forms include Central Pole grotto, Fudou grotto with an oblong or square plane, and the Big Buddha with oval plane and arched roof. Because of the single-lined passageways outside the gates of the grottos, about 15 meters long, it is not easy for the dust storms to intrude, which reduce the damages to the grottos. These grottos have close relationship with the Mogao Grottos in Dunhuang, both of which are Sister Grottos on the Silk Road.
The frescoes inside the grottos include the statues of Buddha, Bodhisattvas, and the paintings of Buddhism stories, flowers and beasts, patterns and ornaments, providers, and other figures. Among them, the No.25 Grotto is the most exquisite and precious one. In the main room are two the paintings about Maitreya and the Pure Land in the West, with grand spectacle and intact composition. Manjusri Bodhisattva riding on a lion, Samantabhadra Bodhisattva riding on an elephant, and the Northern and Southern Heavenly Kings are graphically carved with smooth and skilful strokes, and look vivid and lifelike. In the Big Buddha Hall of the No.6 Grotto, there is a statue of Sakyamuni, 20 meters high, being golden all over the body, which are stunningly beautiful. In the No.29 Grotto chiseled in the West Xia, the male and female providers all wear the hat and clothes of the Western Xia's style, and the inscriptions beside them are also written in the Western Xia language. The frescoes made in those dynasties such as the Five Dynasties, the early years of the Song Dynasty, the Western Xia Dynasty and the Yuan Dynasty, not only follow the themes of the past dynasties, but also adopt some new subject matters such as the Water and Moon Kwan-yin, Datura Stramonium of the Secret Sect of Buddhism and so on, whose artistic style is utterly different from those of the past dynasties.
Inside the grottos chiseled during the Western Xia Dynasty, the image of Sun Wukong has appeared as a monkey in some paintings of the story that Xuanzang, a Buddhist scholar of the Tang Dynasty, overcame difficulties and obstacles and finally reached India for Buddhist scriptures. This may be the first artistic image of Sun Wukong and is more than 300 years earlier than that inthe Pilgrimage to the West.