How the Roman Prison That Once Held Sts. Peter and Paul in Captivity Became a Holy Site

Discover the ancient prison reserved for important state prisoners awaiting their execution where, according to tradition, Sts. Peter and Paul were imprisoned before their martyrdom.

ROME — Hidden below the Church of St. Joseph of the Carpenters, among the ruins of ancient Rome, lies the city’s oldest maximum-security prison: the Mamertine prison.

Originally known as the Carcer Tullianum — possibly named after the Roman kings Tullius Hostilius or Servius Tullius — the Mamertine prison was, according to tradition, built by the legendary fourth king of Rome, Ancus Marcius, in the seventh century B.C.

Although it is believed that it was originally created as a cistern for a spring in the floor of the second lower level — indeed, the word tullius is also Latin for “a jet of water” — the site quickly became an integral part of the Roman justice system for centuries.

“This was an ancient Roman prison from the very foundation of the city of Rome,” Father John D’Orazio, an American priest based in Rome offering pilgrimages with Opera Romana Pellegrinaggi, told the Register.

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