At Xi'an's Chenghuang Temple monks are reviving a kind of music that had almost vanished. The ensemble uses instruments that create a clanging, wailing sound that people who lived during the Tang Dynasty (AD 618-907) would recognize.

"Originally, this music was played for Tang royalty," says Wang Qinghua, a senior Taoist monk. "Then, during times of revolution, the musicians sought refuge in the temples and the music continued to evolve in Taoist and Buddhist temples. Now we're starting to play this music in the temples, and we'll play it on the opera stage of the temple once the restoration is complete."

The temple has only recently re-emerged from long years of depredations. In 1966 the "red guards" smashed religious icons in the temple and turned over the grounds to a flea market. The government returned the temple to Chinese Taoist Association in 2004, and now it's a bustling temple and prime tourist attraction.

Built in the Ming Dynasty 620 years ago, the Taoist temple in Xi'an enthrones the City God, responsible for economic success, natural disasters or epidemics, and even whether someone is born a girl or a boy. In his human life, the City God was a general in the army, named Ji Xin, and he made the ultimate sacrifice for the nation.

Once, the story goes, Han emperor Liu Bang's army was besieged in battle, and Ji swapped his costume with that of the emperor so Liu could slip away. Ji was killed in the emperor's guise.

Now Ji's statue, reinstalled in 2004, depicts a fiery man with a sharp nose and chin, holding a sword up to his chest. The side halls (which are dedicated to the Woman God and Fire God) are full of pendants bearing the names of the lessees that hang the pendants in the temple for a year. Each pendant reflects the prayers of the name-bearer.

Aside from the architectural magnificence of the structural elements - such as the elaborate, sprung, wooden roof supports designed to withstand earthquakes, and the huge wooden pillars fashioned from tree trunks - the temple has a splendid array of rich wooden carvings.

Many of the carvings are cracked and chipped, and that gives them a rare and precious aura. A few are entirely missing, and recreating them is the most complex task in the temple's restoration.

Expected to cost 50 million yuan ($7.4 million), the restoration began in April 2008 and will take 18 months, though the temple will remain open.

"Luckily," says Liu Shitian, abbot of the temple, "we have old pictures and an old manual about the temple's design, so we can faithfully recreate the missing carvings. But we struggled to find craftsmen capable of sculpting these types of carvings. We only managed to find a few artisans, and the youngest one is 72."

There is a lot of work to do. The structures need bolstering, and the main temple hall roof is partly splintered, after it was hit by a Japanese bomb in 1942. The opera house, a standalone structure in the middle of the courtyard, is rickety and rundown.

"Once the restoration is complete," Liu says, "we will put on shows at the opera house with a mixture of cultural and religious themes, including concerts from the Tang era."