It was during the Tang dynasty, China's golden age of economic prosperity and openness, when the caves were the most active. A community of monks, craftsmen and artists lived at the caves, getting their water from the mountain fed Daquan River that flows in front of the cliff. The highly international dynasty saw the introduction of Greek, Hindu and Central and Western Asian cultural influences. Of the over 1,000 Tang era caves, 232 have survived, about half the remaining 492 surviving caves. Most importantly, the Tang dynasty caves are considered the most artistically developed.

Of the 492 caves, 60 are open to visitors, though others maybe opened for a high fee. About 45,000m² of wall paintings and over 2,400 Buddhist sculptures have been preserved in this dry desert climate. The paintings themselves are a priceless resource documenting the changes in lifestyle, religion and culture over a thousand-year period. In 1987 the caves were added to the UNESCO list of World Heritage Sites.

Reflecting the convergence of influences in this area, the architecture in the caves are a mixture of Chinese, Central Asian and Indian styles, which is more apparent in the earlier pre-Tang caves. After the Tang dynasty there wasn't any space left to carve new caves, forcing artisans to re-work older caves. Some stylistic differences to look for are: the older statues tend to be stiffer, the statues appear stronger and the lines are much more defined. Tang sculptures tend to be fluid, the lines are flowing –this is especially clear when looking at the robes of the statues. Whereas earlier statues have severe and dour faces, Tang statues are lively and expressive.

Cave 328 is an example of the melding of two different styles. The sculptures in this cave date to the Tang dynasty, but the ceiling and wall paintings are from the Song dynasty. Inside are three statues of Sakyamuni flanked by two disciples. The artisans who worked on the sculptures, to emphasize that Sakyamuni wasn't Chinese, painted a "typical" Central Asian face on the statue, take a close look at his mustache. To the right of the somber Sakyamuni is a proud looking Ah Nan, one of Sakyamuni's favorites. Standing to Sakyamuni's left is a skinny Jia Ye, his face showing the lines of a hard life. Caves 98 and 100 are also clear examples of two different styles in a single cave.

For architecture aficionados, Cave 96 is a highlight. This is one of the largest caves and has a 34.5mtall Tang dynasty statue of Maitreya, the Buddha of the Future. There's also a pagoda outside that's the same height as the cliff. Only the core of the Buddha is rock, the rock in this area is extremely soft and unsuitable for carving. The craftsman and artisans had to use a terracotta-like plaster pasted over the rock, from which they would mould and carve the intricate details. Smaller statues used a wooden skeleton that was then covered in wheat husks, reeds, hemp and mud before being smeared with plaster. Once carved, painters would paint them with lively colors bringing them to life. Not many of the Tang dynasty sculptures that were made this way have survived, making the remaining ones highly valuable and a focus of preservation efforts.

The wall paintings are definitely the big draw at the caves. If the paintings were lined up end to end they would measure 25km. The paintings are so important as an historic record that scholars have dubbed the ma "mounted library." Some paintings are Buddhist scriptures and sutras, while others illustrate the different ethnicities that passed through Dunhuang. Social hierarchies, traditions, clothing, even music and dancing have been the subject of ancient painters. The different traditions and how they've evolved have been clearly recorded, from important life events such as marriages to mundane activities like farming and business transactions. Caves 47, 112 and 220 have better examples of these paintings.