Vatican Grottoes

Vatican City

The Vatican Grottoes are a series of underground chambers and chapels located under part of the nave of St. Peter's Basilica in the Vatican. They are situated three meters below the current floor, and extend from the high altar to about halfway down the aisle, forming a true underground church that occupies the space between the current floor of the Basilica and that of the old Constantinian basilica of the 4th century.

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