The archaeological complex of Celio Roman houses , located under the Basilica of Saints John and Paul, in Rome, is identified according to tradition, with the place where the saints lived and were buried, after having suffered martyrdom there during the reign of Emperor Julian the Apostate (361-363 AD).
The area, discovered in 1887 by Father Germano of St. Stanislaus, rector of the Basilica, consists of more than 20 underground rooms on various levels, some of which are frescoed with paintings dating between the 3rd century AD and the Middle Ages.
Four main phases of use of the complex have been identified:
First phase The Domus: at the beginning of the 2nd century, the area of the present basilica was occupied by a two-storey luxury residential building, overlooking an alley parallel to the Clivo di Scaurus, equipped with a bathhouse on the ground floor and living rooms on the upper floor.
Second phase The Insula: at the beginning of the 3rd century an insula was built in front of the domus, a multi-storey block of flats for rent, with commercial rooms on the ground floor and small flats on the upper floors, intended for the lower classes.
Third phase The new Domus: between the end of the 3rd and the beginning of the 4th century, the entire block was purchased by a single owner; maybe the upper floors remained divided into rental flats, while the ground floor was used as noble residence for the family that owned the building.
Fourth phase The Domus of the Martyrs: in the second half of the 4th century the Christian tradition places the dwelling of Saints John and Paul here. The construction of the basilica above, built at the beginning of the 5th century by the senator Pammachius, probably identified as the last owner, led to the obliteration of the Roman rooms.