Under the famous dome of St Peter's Basilica, the sound of a chisel hitting stone is ringing out across the rooftops of the Vatican. 

A group of students is learning how to maintain a building that's at the heart of the Catholic faith. 

Below them, thousands of tourists and pilgrims are milling around in St Peter's Square, a vast colonnade wrapping around them.

‌The students have spent the last six months training with stonemasons, carpenters and other workers at La Fabbrica di San Pietro - the Factory of St Peter's. The Scuola di Arti e Mestieri offers courses in masonry, woodworking and other traditional crafts.

‌"From the beginning, we've been discovering new things every day. Either with the Sanpietrini or with our professors, art historians or conservationists, they show us a different side of St Peter's," said Filippo Gallorini, a sculptor who's one of 20 students learning from the Sanpietrini, the workers who look after St Peter's.

‌By picking up a chisel here, of all places, Gallorini and his fellow graduates are following in some very famous footsteps. Some of the best known artists and sculptors in history worked on the construction of St Peter's Basilica, including Michelangelo and Gian Lorenzo Bernini.‌

But with many Sanpietrini retiring in recent years, there was a risk their expertise could be lost forever. Part of the school's mission is to make sure their skills are passed on to the next generation.

‌"For them, it's a unique experience because in the Fabbrica di San Pietro, for about 500 years, there's been a lot of practical knowledge handed down," Dr Assunta di Sante, from the Scuola di Arti e Mestieri, told CGTN Europe. 

"For Sanpietrini of a certain age, it's a privilege for them to be able to teach what they know about St Peter's to these enthusiastic young people. So we give and we also get something back at the same time," he said.

‌With the first round of 20 students set to graduate, the school is planning to expand its classes, including more specialisms such as metalworking. 

The hope is to preserve a building that's watched over this city for generations, for many more centuries to come.

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