Exterior Architecture: Facade, Dome
Saint Peter's is approached via St. Peter's Square, an elliptical forecourt encircled by a Doric colonnade, derived from Greek architecture. It ends at the facade of Saint Peter's which is 376 feet wide and 150 feet high. Designed by Carlo Maderno, the facade features a giant order of Corinthian columns (each 90 feet high) and is topped by thirteen statues - Christ flanked by eleven of the Apostles (excluding Peter) plus John the Baptist. At ground level it is approached by steps guarded by two 18-feet high statues of Saints Peter and Paul.
The Basilica of St. Peter is one of four Major Basilicas of Rome, the others being Santa Maria Maggiore, St. Paul and St. John Lateran, but it is the dome of Saint Peter's - the tallest dome in the world - that dominates the skyline of Rome. Designed largely by Michelangelo, and built during the short but active papacy of Sixtus V (1585–1590) by Michelangelo's pupil Giacomo della Porta, the dome rests on four pendentives and massive piers, each 60 feet thick. It was Michelangelo who increased the size and strength of the load-bearing structure without destroying the central unity of Bramante's original design. Immediate rivals of St Peter's dome include Florence Cathedral of the Early Renaissance, designed by Filippo Brunelleschi and completed in 1434 - for details, see Florence Cathedral, Brunelleschi and the Renaissance (1420-36); Constantinople's Hagia Sophia church, completed in 537; and the dome designed by Christopher Wren for St Paul's Cathedral, finished in 1710. St Peter's Basilica is maintained by the Sampietrini, a specialist group of workers who continually scale and inspect the building's surfaces.