In several days, the members completed this first phase of the mission — removing the gate and wall and rebuilding part of the structure.

With the experience gained from the first phase, they started the second phase of their job — renovating the Guandi Temple in Houji village — with greater skills.

Indeed, this phase called for higher-level skills, said Herwann Rocrou, a French member of the team.

"We needed to lay wall bricks and pave roof tiles," he explained. "These are essential for an experienced mason but quite challenging for a learner."

He said carefully watching the local masons' demonstration and repeatedly practicing are key to fulfilling the job.

He said they have learned some fundamentals in plastering and walling.

"When plastering, the hardest thing is to control the thickness of mortar," Rocrou said. "Too much mortar makes the brick layers uneven and too little makes the wall unstable."

When talking about walling, Rocrou said alignment is another challenge, even with the use of level gauges and plumb bobs.

He later said repeated practice is crucial to tackle the challenges. "After days of practice, I felt I've grasped some skills," Rocrou said. "Now I can build walls according to requirements."

The 23-year-old is a student of archaeology. He said he has been aspiring to repair cultural relics in China for a long time.

"Over the 13 days, I've learned a lot of things — not only masonry but also woodwork and firing bricks and tiles," Rocrou said. "I hope to stay in China for a longer time, to learn to repair cultural relics from the master craftsmen here."