Which of these architects developed the St. Peter’s basilica that exists today, and what were his changes from the original design?

Carlo Maderno’s changes brought St. Peter’s Basilica close to the form seen today: he extended the nave to about 636 feet and added the facade. This changed the earlier central-plan design into a longer, Latin-cross layout. Michelangelo shaped the dome and interior, but Maderno made the listed changes to the basilica’s overall plan.

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