Passage: 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 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 , 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.
 Link Information: The well-known foundation legend of Santa Maria del Popolo revolves around the evil memory of Emperor Nero and Pope Paschal II cleansing the area from this malicious legacy. As the story goes, after his suicide Nero was buried in the mausoleum of his paternal family, the Domitii Ahenobarbi, at the foot of the Pincian Hill. The sepulchre was later buried under a landslide and on its ruins grew a huge walnut tree that ″was so tall and sublime that no other plant exceeded it in any ways.″ The tree soon became the haunt for a multitude of vicious demons harassing the inhabitants of the area and also the travelers arriving in the city from the north through Porta Flaminia: ″some were being frightened, possessed, cruelly beaten and injured, others almost strangled, or miserably killed.″ 

As the demons endangered an important access road of the city and also upset the entire population, the newly elected pontiff, Paschal II, was seriously concerned. He ″saw the flock of Christ committed to his watch, becoming prey to the infernal wolves.″ The Pope fasted and prayed for three days and at the end of that period, exhausted, he dreamt of the Blessed Virgin Mary, who gave him detailed instructions on how to free the city from the demonic scourge. 

On the Thursday after the Third Sunday of Lent in 1099, the Pope organised the entire clergy and populace of Rome in one, impressive procession that, with the crucifix at its head, went along the urban stretch of the Via Flaminia until it reached the infested place. There, Paschal II performed the rite of exorcism and then struck the walnut tree with a determined blow to its root, causing the evil spirits to burst forth, madly screaming. When the whole tree was removed, the remains of Nero were discovered among the ruins; the Pope ordered these thrown into the Tiber.

Finally liberated from the demons, that corner of Rome could be devoted to Christian worship. Paschal II, to the sound of hymns, placed the first stone of an altar at the former site of the walnut tree. This was incorporated into a simple chapel which was completed in three days. Answer: Pope Paschal II
Output: Who designed the actual building for which a police station in Rome opposite it was used for the exterior?