A crane hoisted massive oak trusses from a barge and onto Notre Dame Cathedral on Tuesday in a spectacular operation to rebuild the fire-ravaged monument and bring it back to life by December 2024.

With trusses weighing seven to seven and a half tonnes, the delicate operation drew crowds along a bridge over the Seine River and on its banks.

“I think it’s a magical moment for a lot of Parisians this morning,” said Transport Minister Clement Beaune, who said the Seine will be at the centre of the Paris Olympics in 2024.

Jean-Louis Georgelin, appointed by French President Emmanuel Macron to oversee Notre Dame’s reconstruction, said even the heavy traffic expected during the Games will not stop work on the cathedral.

“We will work for the cathedral during the Olympics in order to be ready in December 2024,” he said. “This is our goal.”

Notre Dame, which overlooks the historic core of Paris from an island on the Seine, was consumed by flames in 2019. It was decided to rebuild the monument using traditional methods.

Expert carpenters used medieval techniques to construct the trusses, which measure 46 to 52 feet wide and 39 to 43 feet high.

Guided by ropes, the trusses were placed on the roof around the area of the spire, which crumbled in cinders during the fire, and the two arms of the transept – the wooden skeleton of Notre Dame.

A statement said the cathedral’s silhouette, now enmeshed in scaffolding, should emerge on the skyline as work advances.