St Peter's Basilica

Constantine built the first basilica in the 320s over a modest first-century grave marked in a pagan necropolis; twentieth-century excavation under the high altar found the shrine and bones the tradition names. The Renaissance rebuilding ran from 1506 to 1626 and consumed Bramante, Raphael, Michelangelo and Bernini in turn. The indulgence campaign that paid for it triggered Luther's Ninety-Five Theses.