• The pantheon was originally built in 28 BC by Marcus Agrippa

 

• It was restored many times over the centuries. The bronze doors themselves were restored by Pope Pius VI who reigned from 1559-1565

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• When the construction of the baldachin at St. Peter's stalled because of lack of bronze, Pope Urban VIII (1623-1644) of the Barberini family had the trusses and girders melted down for reuse. This was the cause of the famous saying: "What the barbarians didn't do, the Barberini did."
 

• The floor was renovated by Pope Pius IX in 1846-1878