Dome of St. Peter's basilica found stronger than expected
April 06, 2011
Structural engineers examining the dome of St. Peter's basilica have found that the building is even stronger than previously believed.
Using high-tech instruments, the study found that the stone of the dome is supported by 7 iron rings, whereas it had been thought to have only 2 such rings. The dome, built in the 16th century, was constructed using the equivalent of today's reinforced concrete.