Carcer Tullianum (Mamertine Prison)

    /person normally

What you'll do

Experience one of the most fascinating and crucial monuments of the Roman period. With its great historical and archaeological wealth, it is worth delving underneath the Church of St. Joseph ‘‘the Carpenter’ to explore and learn about the history of the Mamertine Prison.

Explore the Carcer Tullianum with the OMNIA Vatican & Rome Pass

  • Includes entry to Carcer Tullianum, one of Rome's hidden treasures.
  • Free multimedia device in Italian, English and Spanish. 
  • This attraction is included with your OMNIA Card, which allows you free entry to Vatican attractions, as well as the Rome Hop-On Hop-Off Bus.

The first signs of the place date back to the ninth century BC and the prison is situated underneath the Church of St. Joseph. With its low ceilings, dark cramped rooms, and untouched feel, you'll leave fulfilling your morbid curiosity. The Tullianum comes with ancient Roman myths of the great St. Peter, baptizing fellow martyrs at the foot of the spring, this created a devotion that attracted pilgrimages, even to this day. 

Your visit to the Carcer Tullianum is supplemented with a multimedia guide that includes the use of a tablet, helping you gain a better insight on the reconstruction, the history, the ancient traditions as well as insights of items that were found during excavations. The tour is available in English, Italian and Spanish.


  • A plaque listing the martyrs
  • The Circular lower room (Tullianum)
  • The Upper Room (Carcer)
  • An altar symbolizing St Peters execution
  • View of the Roman Forum from outside the prison

Did you know

  • As a means of getting the martyrs inside the prison, they simply dropped them into their cell through a hole in the ceiling. 
  • The Carcer Tullianum was for a long time the only public prison in ancient Rome. it was reserved for important state prisoners, more often than not they have put in there prior to their execution.
  • There is a Roman legend that states St Paul and St Peter were both imprisoned there before they were executed, to this day it is unknown as to whether it's in fact true or myth
  • Another legend is that the spring found in front of the altar in the Tullianum was flooded by St. Peter so that he could baptize his fellow prisoners and guards.
  • The cross found on the alter is the wrong way up because it is believed St Peter asked to be crucified upside down so that he wasn't emulating christ. 

Things to see

The Tullianum, also known as the circular lower room, is the cell where the prisoners were thrown into before execution. The altar that is backed with the belief that St Peter baptized his fellow prisoners is situated at the back. 

Also known as the upper room, has a plaque mounted to the wall displaying all the most celebrated prisoners. Plus you'll find a hole in the floor that is now covered up for safety reasons - the hole falls directly into the Tullianum, this was the method in which they dropped the prisoners into the cell. 

The small altar and upside-down cross found at the back of the cell symbolizes St Peters's execution, which is accompanied by the bars that he was supposedly chained to.

Know before you go

Getting in: show your OMNIA Card for entry.

This attraction is included with your OMNIA Card, which allows you free entry to Vatican attractions, as well as the Rome Hop-On Hop-Off Bus.

Where you'll be

Operating hours

Daily: 9.30AM-5PM (last admission 4.30PM)

Dreaming of that Rome city break?

Sign up to receive top travel tips

  • Thick check Icon
Visitor Out Of Test