The Mogao Grottoes, also known as "Thousand Buddha Caves", is located on the Rattling Sand Mountain (mingsha shan) of Dunhuang County in Gansu Province, China. It is one of three noted grottoes in China for its fabulous frescos and statues.
The construction of the Mogao Grottoes began in the period of the Sixteen Kingdoms (about 366 A.D.), and the endeavor continued through the later dynasties, including the North Dynasty, Sui, Tang, Five Dynasties, Western Xia and Yuan. Today, the grand dimension of the site is shown by 735 caves, with murals covering 45,000 square meters and colored clay statues 2,415 square meters. It is the largest and richest extant treasure house of Buddhist art in the world.   
Located on the precipice of the Rattling Sand Mountain, the caves are divided into south section and north section. The south section, as the main part of the Mogao Grottoes, is for religious activities of monks. Each cave contains wall paintings or sculptures in this section. The north section is the area in which the monks live, cultivate themselves according to the religious doctrine and bury the deceased peers. There are only five caves containing frescos or statues in this section.
The soft soil of the caves' location is unsatisfactory to produce stone statues. Thus, the majority of statues in the grottoes are wooden-body clay statues with the exception of four big stone-body clay statues of Buddha. Whether in single or group forms, the Buddhist figures are so delicately made and life-like that they become a harmonious integration with the surrounding murals. Frescos can be seen on the walls and ceilings of caves and inside the niche for Buddha. The motif of these paintings covers a wide range with profound depth, such as joss, Buddhist stories, spirits, and decorative patterns. Social lives during that age are also displayed in the murals, including hunting, farming, spinning, transportation, battle, construction, dancing, wedding and funeral. Some paintings are bold and broad in style while others are magnificent with resplendent colors, reflecting the artistic styles and features in different periods.
Apart from those refined sculptures and murals, the caves were also constructed exquisitely in varied forms and sizes. The largest one, No. 16 Cave, covers 268 square meters while the smallest one, No. 37 Cave, is only 20-30 cm in height. Outside the grottoes, there were wooden temples connected with corridors and plank roads in early days. However, they were not fully preserved and can be barely seen today.
In modern times, the Cave of Buddhist Scriptures was accidentally discovered and the Mogao Grottoes re-attracts attention from all over the world. Tragically, a large amount of rare scriptures were stolen. A new branch of international studies, the Dunhuang Studies, has come into being for the research on scriptures of this cave and Dunhuang's art.
In 1961, the Mogao Grottoes was listed among the first group of Cultural Relics of National Importance under the Protection of the State by the State Council, and it was listed among the World Cultural Heritage Sites in 1987.