The restoration lasted over a year, and in that time the cathedral was turned into a bit of a building site, with a maze of scaffolds set up on the altar and transept.
Local experts from the Italian Ministry of Culture led a series of interventions, starting with the removal of a thick layer of dust that had accumulated on the mosaics over the years.
Then they repaired some of the tiles that had lost their enamel and gold leaf, making them look like black spots from down below.
Finally, they intervened in the areas where the tiles were peeling off the wall and secured them.
Working on the mosaics was a challenge and a big responsibility, says Father Nicola Gaglio.
He has been a priest here for 17 years and has followed the restoration closely, not unlike an apprehensive dad.
“The team approached this work almost on their tiptoes,” he tells me.
“At times, there were some unforeseen issues and they had to pause the operations while they found a solution.
“For example, when they got to the ceiling, they realised that in the past it had been covered with a layer of varnish that had turned yellowish. They had to peel it off, quite literally, like cling film.”
