Who designed the dome of Saint Peter's Basilica in Rome?

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Catholic AnswerAttached below is the Vatican's website for St. Peter's including the full history. Pope Nicholas V decided to rebuild the ancient Basilica originally build on St. Peter's tomb by the emperor Constantine. From the time that Pope Nicholas started rebuilding, it took 150 years (until 1612) to finish the Basilica, it was the work of many people and many Popes.