The story starts in the Circus of Nero, where tradition holds the Apostle Peter was crucified upside down around 64 AD and buried in a simple plot on Vatican Hill. Constantine built Old St. Peter’s over the grave in the fourth century, and by the 15th century its walls were leaning. In 1505 Pope Julius II decided to demolish it for a new church big enough for the tomb he had commissioned from Michelangelo. Paying for it meant selling indulgences, and the German friar Johann Tetzel’s aggressive sales campaign provoked Martin Luther and the Protestant Reformation. Bramante laid the foundation stone in 1506, but Raphael, Peruzzi, and Sangallo kept redrawing the plans, Rome was sacked in 1527, and Bramante’s piers began to crack.

Michelangelo took over in 1547, in his 70s, simplified the design, and replaced a hemispherical dome with a taller ovoid dome on 16 ribs that pushed its weight down into the piers instead of outward. Under the Counter-Reformation, Carlo Maderno stretched the church into a Latin cross with a long nave and a broad facade that hides the lower dome from the square. The shell was finished in 1626, 120 years after it began. Bernini then spent some 50 years making the space readable, with the bronze baldacchino nearly 30 meters tall and the Cathedra Petri. In the 2020s a Vatican partnership with Microsoft mapped the basilica from over 400,000 drone photos and rebuilt it in Minecraft for the 2025 Jubilee.

• Why a Pantheon-style dome on four standalone piers would have burst, and how an egg shape solved it
• The twisted columns of the baldacchino, modeled on ancient columns Constantine brought from the Temple of Jerusalem
• Moving the 360 ton obelisk from Nero’s circus in 1586 with 44 capstans, 900 men, and 75 horses under an order of total silence
• Benedetto Bresca, the sailor who broke the silence to shout water on the ropes, and the Palm Sunday privilege his hometown won
• Cherubs that look normal-sized from the nave but stand over two meters tall