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Regio III - Insula I - Basilica Cristiana (III,I,4)

The Christian Basilica was discovered and excavated in 1939, by Guido Calza. He found a late-antique structure (opus vittatum, opus latericium, rubble masonry), built in and on top of pre-existing, Trajanic structures (opus latericium and opus mixtum), from south to north:


From the Decumanus vestibule A is reached (w. of entrance 3.48). The vestibule leads to a central "nave" (B). To the north-east of the "nave" are rooms F, G and H. These rooms originally formed part of the baths to the north-east (they had raised floors, suspensurae). In the entrance of each room are two columns and a marble threshold. On one of the columns in room F is the inscription:

VOLVSIANI V(ir) C(larissimus)

The column comes from the marble depot in the adjacent building, the Tempio dei Fabri Navales, where the same text was found on several columns. This Volusianus lived in the fourth or early fifth century AD.

The south-west wall of the "nave" is a row of five columns. In the north-west wall are a marble threshold and step, leading to room C, that is at a lower level. In this room an apse was built. In the apse are two semicircular wall-niches for statues (starting at 1.05, average h. 2.14, d. 0.72, w. 1.35). Their position is curious. They are not positioned on the axis of the room, the "nave" and the vestibule. Instead, they are on a diagonal axis, from the south corner of the room to the point between the two niches. The floor of rooms B and C was not found by the excavators. They did find many marble fragments however. Clearly the building had been plundered.

A few steps lead from room C to a small room to the north-east, flanked by two more rooms. A door in the southern room leads to the Trajanic caseggiato with courtyard (see above), of which five rooms around courtyard M were preserved.

To the south-west of A and B is another "nave" (E), that was also reached from the Decumanus (w. of entrance 2.66). A door in the south-west wall leads to rooms of caseggiato III,I,5 (room N). To the north-west is room D, with an apsidal back wall. In the apse (w. 3.07) are three wall-niches (w. 1.35, 1.46 and 1.96, d. 0.48). The central one is rectangular, the flanking ones are semicircular. In each niche a basin and a hole for a water-pipe were found. A large basin (height c. 0.80) must have been standing in front of the niches, set against the entire apse. In the outside of the apse is a small rectangular wall-niche. In the south wall of the room is a small apse, with a basin. The apses and niches had marble revetment. Between the two apsidal rooms (D and C) are four columns and a doorway.

In the south-eastern entrance of room D are two columns, supporting an architrave with an inscription. The architrave was found near the building. It fits perfectly on its present spot. It is made of two marble blocks and has a total length of 3.85. One of the blocks had been used as a threshold. Before that it carried an inscription. Traces of a single line, containing names, have been read:

[---]S ALEXANDER [---] AMMIVS [---] IGENIVS [---] V C [---] STINIANVS

On the side facing room E is an inscription, that Calza read and understood as follows:


(so Calza suggests that the first two letters of the second line are a mistake and should be neglected).

In the building the following objects were found:

  • A mensa ponderaria (a slab with cavities to check compliancy to standard weights).
  • A marble statue of Fortuna, found in room C.

Plan of the building. After SO I.


Heres has established that the last phases of the building belong to the fifth century. Most of the masonry belonging to the "basilica" belongs to the first half and perhaps the first quarter of that century. The apse in room C was added a few years later. The capitals in the building were made c. 420 AD.

Click here to open the plan published by Heres in a new window (Heres 1982, fig. 82).

Gobbi came to different conclusions after research in the late 1990's. According to her the apses in rooms C and D are contemporaneous. She believes, that after the addition of the apses the building was a domus. She maintains that rooms A, B, F, G, and H were added later, when columns were also installed. She prefers a date in the fourth century. Unfortunately she did not start an explicit discussion with Heres.

Click here to open the plans published by Gobbi in a new window (Gobbi 1998, Tav. II and III).


We have seen that Calza suggested this for the inscription on the architrave:


In the first line the four rivers of paradise are mentioned (Genesis 2, 10-14). According to Ambrosius Christ was the source (fons) of the four rivers, and thus the source of eternal life (De Paradiso 3, 13-14; Erat fons qui inrigaret paradisum. Qui fons nisi dominus Jesus Christus, fons vitae aeternae sicut Pater? ... Et dividitur fons in quattuor initia: nomen est uni Phison ... et nomen secundo Geon ... et flumen tertium Tigris ... et flumen quartum Eufrates ...). The four rivers were likened by christian authors to the four gospels, and were according to Calza also related to baptism (Cyprianus, Epistulae 73, 10; Has arbores rigat quattuor fluminibus id est evangeliis quattuor quibus baptismi gratia salutari et caelesti inundatione largitur; see also Augustinus, De Civitate Dei 13, 21).

According to Calza the (illiterate?) man who hacked out the inscription made a mistake at the beginning of line two: he started again with the word TIGRIS. The names of the four rivers are in the nominative, so sunt may be added, leading to the translation: "In Christ are Geon Fison Tigris Euphrates. Drink from the sources of the Christians".

Alternative translations are:

A horizontal line to the right of the vertical line of the first T in the second line has suggested to Egger that it is an F, and he suggests FL(uminum) C(h)RI(st)IANORVM ("Geon, Fison, Tigris and Euphrates are in Christ. Use the water of the rivers of Christ"). In reality this horizontal line is an optical illusion, a shadow. The interpretation PEREGRINIANORVM by Mercati also has to be rejected.

For the correct reading of the inscription we must thank Burzachechi. His solution is now almost universally accepted. He argues that the letters TI in the second line cannot be understood as an error. It would have been easy to remove the two shallow letters. Also the person who had ordered the inscription would never have accepted this embarrassing mistake. There is furthermore not enough space for the letters ST. The first word of the second line is TIGRI[N]IANORVM ("Use the sources of the Tigriniani"). Burzachechi suggests that the Tigriniani were either a Christian family, or heretics, the followers of a certain Tigrinius or Tigrinianus. There may also be an allusion to the name of one of the four rivers in the first line, the Tigris.

Marrou points out, that heretics are documented very well in ancient literature, but Tigriniani are not among them. He points to a priest named Tigrinus, who was active during the papacy of Leo I (440-461 AD). He oversaw the building of a church on the Via Latina. His funeral inscription states, that he repaired sacred buildings (Diversis reparo tecta sacrata locis, culminaque hic lapsis trabibus totumque novendo, promerui superas laetior ire domos). The repairs may have been necessary after an earthquake in 442-443 AD. Parallels for the form Tigriniani are the Galbiani, Augustiani and Christiani, followers / supporters of Galba, Nero, Christ.

If this Tigrinus was indeed active in Ostia, then the inscription may have been added later to the architrave, perhaps when the apse in room C was built (an apse that has an axis running in the direction of the architrave).


According to Calza the building had in the final phase become a Christian church. He dates it to the period of Constantine and suggests that this is the church of Peter, Paul and John the Baptist that, according to the Liber Pontificalis, was donated to Ostia by Constantine. Calza then suggests, that the apsidal room behind the inscription was a baptisterium.

Calza's dating and interpretation of the building have been criticized by many authors. The building lacks many features of a basilica, such as the right nave and an altar, and the statue-niches in room C do not belong in a church. The basins are not suited for baptism, which required total submersion. Baptism was related to the river Jordan, not the rivers of paradise. Room D was a nymphaeum. In the late 1990's the basilica of Constantine was located by Michael Heinzelmann, outside the Porta Laurentina.

The building was after Calza interpreted as:


The presence of relatively small rooms to the north-east and south-west, in combination with accentuated rooms (nymphaeum D, possible triclinium C with a semicircular dining-couch (stibadium)) suggest that the building was in its last phase a domus. It is true that there are no parallels for the plan amongst the larger known late-antique domus in Ostia, but it is dangerous to judge only on the basis of what we know.

But was the building a domus when the inscription had been chiselled in the architrave? That idea is problematic. The sources (fontes) in line two are compared to the rivers of paradise in line one. How can these rivers, emanating from Christ in the form of the gospels and providing eternal life, be likened to the niches of a nymphaeum in a mere house?

The reference to the nymphaeum must have had a deeper, Christian meaning, and it does not seem to have been baptism. This meaning is found, if the building was a guest house for pilgrims, who came to Ostia and of course Rome, to visit holy sites. In the guest house they would be provided with water, food and a place to sleep in the small rooms. The use of these "sources" would enable the pilgrim to tap the sources he came to visit, the holy monuments.

Nevertheless the link between the two lines remains unsatisfactory, forced. This may well be the result of an "intended pun": the wish to link the name of one of the rivers of paradise, the Tigris, to the name Tigrinus ("he who dwells near the Tigris").

Photographs and drawings

A reconstruction drawing of the building, seen from the south.
Calza 1940, fig. 16.

A reconstruction drawing of the building,
seen from the south.
It is not certain that all rooms had a roof.
Calza 1940, fig. 17.

Room D, seen from the back (north-west), after the excavation.
To the right is the mensa ponderaria. Pensabene 1998, fig. 45.

Room E, seen from the Decumanus (south-east), after the excavation.
Pensabene 1998, fig. 46.

Vestibule A, "nave" B and apse C, seen from the Decumanus (south-east).
Note that the mensa ponderaria has been placed in the vestibule.
Photograph: Jan Theo Bakker.

To the left room E and the architrave with the inscription, to the right "nave" B and apse C,
seen from vestibule A (south-east). Photograph: Jan Theo Bakker.

"Nave" B and apse C, seen from vestibule A (south-east).
Photograph: Jan Theo Bakker.

In the foreground the piers supporting the architrave with the inscription,
to the left room D, to the right room C. Seen from room E.
Note that the niches in room C are facing the viewer.
Photograph: Jan Theo Bakker.

The architrave with the inscription, seen from room E.
Photograph: Jan Theo Bakker.

The left part of the inscription on the architrave.
Burzachechi 1959, fig. 4.

The inscription VOLVSIANI VC on a column in room F.
Photograph: Eric Taylor.

[jthb - 27-Sep-2004]