Nanchan Temple's Great Buddha Hall spent more than a millennium in the mountains before the modern world found it. In the 1950s, architectural historians surveying China's ancient buildings identified the hall and, in 1961, it was officially recognized as the oldest standing timber-frame building in the country. An inscription on one of the beams confirmed its construction date of 782 AD, during the Tang dynasty. A second inscription recorded a renovation in 1086 under the Song dynasty, when all but four of the original square columns were replaced with round ones. Then in 1966, an earthquake damaged the building, and the subsequent restoration gave scholars an extraordinary opportunity: the chance to study a Tang dynasty structure piece by piece, documenting every joint, bracket, and beam.

The Great Buddha Hall is not a grand building. It measures just 11.75 meters across and 10 meters deep, a three-bay square hall with a hip-gable roof supported by twelve pillars planted directly into a brick foundation. There is no ceiling, no interior columns, no struts between the outer columns -- features that mark it as a low-status structure in the Tang architectural hierarchy. But these very limitations make it invaluable. The hall preserves Tang dynasty construction techniques in their most unadorned form: the longer central front bay, camel-hump braces, five-puzuo bracket sets, and a yuetai platform. Every detail is a primary source document in wood, recording how Chinese builders worked twelve centuries ago.

Alongside the architectural structure, Nanchan Temple houses seventeen original Tang dynasty sculptures arranged on an inverted U-shaped dais. The central figure is a cross-legged Sakyamuni Buddha seated on a sumeru throne decorated with sculpted lions and demigods, his massive halo adorned with lotus flowers and celestial beings. Flanking statues include bodhisattvas, Samantabhadra riding an elephant, Manjushri on a lion, two of the Buddha's disciples, heavenly kings, and attendants. The hall also contains a small Northern Wei stone pagoda carved with Buddhas on every surface. Not all of these treasures survived the modern era intact. Three of the original Tang sculptures were stolen in 1999, and the stone pagoda was taken in 2011. None have been recovered -- a reminder that the threats to ancient sites come not only from emperors and earthquakes but from thieves.

The 1974 restoration of Nanchan Temple was an extraordinary undertaking. Defined by the Chinese term Luo-Jia-Chong-Xiu -- roughly meaning to disassemble the entire structure and reassemble it -- the project required removing every component, repairing or replacing damaged elements, and rebuilding the hall according to its original Tang dynasty design. Weathered columns were reinforced with traditional metal hoops and experimental epoxy resin injections. Scholars removed a dwarf pillar that later dynasties had added, revealing the original Tang-era diagonal support called Cha-Shou. The eave rafters, which had been trimmed during previous restorations, were extended back to their original length based on the dimensions of the platform. Most controversially, the team removed a brick facade of arched windows and doors -- a later addition, since bricks were uncommon in Tang construction -- and restored the original wooden facade using the nearby Foguang Temple as a guide.