The Mamertine Prison, or Carcer Tullianum, is considered the oldest prison in Rome and holds great historical and religious significance. It is located beneath the Church of San Giuseppe dei Falegnami, near the Roman Forum. Built in the 7th century B... read moreCE by King Ancus Marcius, the prison was used to detain important prisoners of war and political figures prior to their execution. The two-tiered structure includes an upper chamber known as the Carcer and a lower, darker chamber called the Tullianum, where prisoners were lowered through a hole in the floor.

Over time, the prison became associated with early Christian history. According to tradition, Saint Peter and Saint Paul were both held here, and it is said that Peter miraculously caused a spring to appear in the Tullianum so he could baptize fellow inmates. Other notable prisoners included Vercingetorix, leader of the Gauls, and Jugurtha, king of Numidia. These associations have transformed the prison into a place of religious reverence, making it both a historical and spiritual site.

Today, the Mamertine Prison is open to visitors who wish to explore its ancient stone chambers and learn about its layered past. Exhibits and audio guides provide context about the site’s Roman and Christian history. Visiting hours typically run from 9:00 AM to 5:00 PM, with the last entry at 4:00 PM. While compact in size, the site offers a powerful look into Rome’s darker past and is a compelling stop for those interested in the city’s early history. Due to its layout and depth, accessibility is limited for those with mobility issues.