Shooting began on June 4, 2008 in Rome under the fake working title "Obelisk".
Roman Catholic Church officials found The Da Vinci Code offensive and forbade filming in their churches, so these scenes were shot at Sony.
The Caserta Palace doubled for the inside of the Vatican, and the Biblioteca Angelica was used for the Vatican Library.
When recreating the interior of St. Peter's Basilica, production designer Allan Cameron and visual effects supervisor Angus Bickerton recognized the 80 feet tall soundstages were only half the size of the real church. They rebuilt the area around and the crypts beneath St. Peter's baldachin, including the bottoms of the columns and Saint Peter's statue, and surrounded it with a 360 degree greenscreen so the rest could be built digitally.
Cameron had twenty crew members photograph as much as they could inside the Sistine Chapel, and had artists sketch, photograph and enlarge recreations of the paintings and mosaics from the photographs.
Cameron chose to present the Sistine Chapel as it was before it was cleaned up, because he preferred the contrast the smoky, muted colors would present with the cardinals. Although the chapel was built to full size, the Sala Regia was made smaller to fit inside the stage.
The Saint Peter's Square and the Piazza Navona sets were built on the same backlot; after completion of scenes at the former, six weeks were spent converting the set, knocking down the Basilica side and excavating 3 1/2 feet of tarmac to build the fountain. As there had been filming at the real Piazza Navona, the transition between it and the replica had to be seamless.
To present the Santa Maria del Popolo undergoing renovation, a police station in Rome opposite the real church was used for the exterior; the scaffolding would hide that it was not the church. Cameron built the interior of Santa Maria del Popolo on the same set as the recreated Santa Maria della Vittoria to save money; the scaffolding also disguised this. The film's version of Santa Maria della Vittoria was larger than the real one, so it would accommodate the cranes used to film the scene.
To film the Pantheon's interior, two aediculae and the tomb of Raphael were rebuilt to scale at a height of 30 feet, while the rest was greenscreen. Because of the building's symmetrical layout, the filmmakers were able to shoot the whole scene over two days and redress the real side to pretend it was another.
The second unit took photographs of the Large Hadron Collider and pasted these in scenes set at CERN. |
I guess they had to compromise on that to even step into Rome. 
