Top sights to see and tips for avoiding the lines! Restaurant recommendations--jump to them HERE. St. Peter's Basilica This basilica is huge - it's meant to be impressive as the home base of the Catholic religion and represent the power of the Church. The basilica was constructed on the remains of Constantine the Great's basilica (originally built in the 4th century but taken down to make space for St. Peter's basilica) starting in 1506, with construction and interior decora