I definitely consider it to be the highlight of my most recent visit to Rome: a trip to the Catacombs of Saints Marcellinus and Peter, which were reopened to the public in 2014. I had already been to the Catacombs of San Callisto on the Via Appia once, but those of Santi Marcellino e Pietro on the Via Casilina are much more impressive. As our guide correctly stated: the former catacombs are best known because of the stories surrounding them and because of the famous Crypt of the Popes, but the latter catacombs have the best fresco art in all of Rome. This art is mostly from the fourth century and it has been thoroughly cleaned recently, using the most modern laser technology. Apparently the Republic of Azerbaijan provided financial assistance, for reasons that our guide could not reproduce. The Azerbaijani assistance is commemorated on a plaque which you can see as you enter the catacombs and go down the stairs to the lower levels.
Please note that you can only visit these catacombs with a guide and that reservations are compulsory. These can be made at the catacombs’ official website. Guided tours in English are available. Our guide, Flavio, was very good and really took his time to explain everything about the history of the complex. The catacombs are located about four kilometres west of the Stazione Termini railway station. If you want to go on foot, remember that it is not only a stiff walk, but that it takes you through a part of Rome that is of no historical interest whatsoever. It is much better to take the little electric train (trenino) from the Stazione per le Linee del Lazio, which can be found at the south side of the Termini station. ATAC tickets are valid on this line. The trenino will take you to the Berardi stop in about 15 minutes. This stop is directly opposite the catacombs. The trenino offers a very convenient way of travelling.
The address of the catacombs is Via Casilina 641. In Antiquity, this road was known as the Via Labicana. The location itself, at the third milestone, was known as Ad Duas Lauros (“at the two laurels”). The imperial horse guards – equites singulares Augusti – had their burial grounds here, in the green area surrounding the current complex, which is now known as the Villa de Sanctis. The horse guards supported the usurper Maxentius against the future emperor Constantine and were defeated in 312 at the Battle of the Milvian Bridge. Constantine then punished the equites singulares Augusti by disbanding their units, giving their barracks to the Church (the church of San Giovanni in Laterano would be built over this camp) and destroying their cemetery. The new emperor was not mild in victory. If your guide allows you some time to admire the pieces of marble with Latin texts in the room directly behind the entrance, you will notice that a lot of them are from funerary monuments for horse guards; watch out for the words EQ[VES] SING[VLARIS] AVG[VSTI]. All of the inscriptions are broken, and this was likely a deliberate act of vandalism on Constantine’s part.
By the time Constantine deposed his rival Maxentius and took control of Rome, Christians had already been using the catacombs at the two laurels for perhaps three decades. Our best guess is that they started using this location for underground burials just before the emperor Diocletianus (284-305) launched the final round of anti-Christian persecutions in the Roman Empire. It is evident that many wealthy Christians were buried here. Not all of the rooms (cubicula) and tombs (the simple ones, just a niche in the tufa covered with a slab, are called loculi) are decorated with frescoes. But those that are, have incredibly rich decorations, executed by what must have been the finest fresco painters in all of Roman Italy. Our guide took us straight to the best work in the entire catacombs, a fresco of Jesus Christ with Saints Peter and Paul, with smaller images of Saints Marcellinus, Peter (not the apostle!), Tiburtius and Gorgonius below them. The fresco was painted on the ceiling of the cubiculum and is in excellent condition.
We do not know much about the aforementioned Saints Marcellinus, Peter, Tiburtius and Gorgonius. Marcellinus seems to have been a priest, Peter is often called an exorcist. Both were victims of the persecutions instigated by Diocletianus, but no biographical information about the two is known. A few decades later, Pope Damasus (366-384) wrote epigraphs for the two martyrs, claiming that the person who had them executed told him about the double murder when the pope was still a child. Marcellinus and Peter were buried near the third milestone on the Via Labicana. There was already a tomb here where Saint Tiburtius, reportedly martyred in 286, had been buried. This is probably not Saint Cecilia’s brother-in-law of the same name, but a different Saint Tiburtius (see Rome: Santa Cecilia in Trastevere). Not much is known about this Tiburtius either, and the same is true as regards Gorgonius. Pope Damasus wrote epigraphs for both of them, but evidently had no biographical information whatsoever. The Pope claimed that Gorgonius “cares for the altars of Christ”, and if we take that literally, we may assume he had been a deacon.
Use of the catacombs for burials was discontinued in the early fifth century. In pagan Rome, inhumation had mostly replaced cremation by the third century. According to the law, people had to be buried outside the city walls for religious reasons (it was the sensible thing to do for hygienic reasons as well, but the Romans do not seem to have realised this). This is why we find the dozens of catacombs of Rome all on the outskirts of the city, outside the third century Aurelian Walls. Both Christians and pagans were buried at most catacombs, but when Christianity became the state religion, the Christian population gradually began to prefer being buried in or near the various churches, which were by now mostly located in the city itself (there were exceptions). The Catacombs of Saints Marcellinus and Peter were therefore no longer used to bury the dead.
This leaves us with an underground complex of some 18.000 square metres and some 4,5 kilometres of tunnels (we were glad our guide knew his way around here blindfolded). The catacombs became an important destination for pilgrims from the fifth century onwards. Our guide showed us graffiti made by pilgrims who used a Runic script, so they must have been from Scandinavia. In the ninth century, travelling along the Via Labicana became too dangerous because of the presence of brigands. The catacombs – that is: practically all catacombs – lost their importance as the relics of the saints and martyrs were brought to churches within the city walls (see Rome: Santa Prassede for some more information).
Our guide asserted that the Catacombs of Saints Marcellinus and Peter are exclusively Christian. This may be true for the parts that he showed us, but excavations in the 2000s have demonstrated that some 2.500 people from the pre-Christian era were buried here as well. These people were definitely not Christians; they seem to have been associated with the equites singulares Augusti mentioned above. The prevailing theory is that they were the victims of several epidemics. The Roman Empire was frequently struck by outbreaks of the plague (probably smallpox or measles). A particular severe one was the Antonine Plague, which claimed tens of thousands of lives during the reign of the emperor Marcus Aurelius (161-180). Many of the people buried at the catacombs may have been victims of this plague. They may have been the horse guards themselves, their wives and their children. The bodies were covered in lime plaster, and traces of sandarac, frankincense and amber have been found.
Unfortunately, visitors are not allowed to take photos. Whether this is because the catacombs are a sacred place or because of commercial reasons is not entirely clear. Some pictures of the frescoes from the catacombs can be found on Wikimedia Commons, but I would recommend anyone to go and visit the Catacombs of Saints Marcellinus and Peter themselves.
Mausoleum of Saint Helena
A few words about the Mausoleum of Saint Helena now, a partly ruined building that is part of the complex. It once housed a sarcophagus which held the body of Saint Helena, mother of the emperor Constantine. The so-called Sarcophagus of Helena can now be found at the Museo Pio-Clementino, which is part of the Vatican Museums. The sarcophagus is quite spectacular. It is entirely made of Egyptian porphyry and depicts scenes of Roman cavalry riding down barbarian enemies, some of whom seem to be prisoners (they have their hands tied behind their backs). Because of the violent nature of the scenes, it has generally been assumed that the sarcophagus was originally intended for the emperor himself. It has therefore been claimed that the building that we now know as the Mausoleum of Helena was initially erected to become Constantine’s own final resting place. Apart from the sarcophagus, which indeed seems highly improper for a devout Christian woman, there is no direct evidence for this theory.
In any case, Constantine ultimately chose to be buried in the church of the Holy Apostles in Constantinople. After defeating his rival Licinius in 324, Constantine had begun construction of a new capital on the foundations of ancient Byzantium. The emperor decided to name the city after himself. The new city was formally consecrated in a ceremony held on 11 May of the year 330. When the emperor died seven years later, he had long abandoned any intention of being buried in Rome, if he ever had this intention at all. The spectacular circular mausoleum of which we can still admire the remains had by that time already become his mother’s final resting place. Helena’s exact year of death is unknown, but she probably breathed her last breath between 327 and 330.
The mausoleum must have been completed by 330 at the latest. It was part of a large circiform basilica (i.e. shaped like a Roman circus), which most likely did not function as a church, but was meant as a “funerary basilica”. Other examples of such circiform basilicas can be found at San Sebastiano fuori le Mura, San Lorenzo fuori le Mura and Sant’Agnese fuori le Mura. The basilica at the two laurels was built with the apse facing the west. It had a length of some 65 and a width of 29 metres. Almost nothing of this basilica remains today. To the left (i.e. west) of the Mausoleum of Helena visitors may notice a few traces of the rectangular external narthex. This is actually best viewed on Google Maps. Excellent reconstructions of the basilica have been made. See this picture to get an idea of the plan and this one, this one or this one for a reconstruction in 3D. Whether the central part of the basilica had a roof is up for debate. It may have just been an enclosure with covered aisles. Part of the complex was an older mausoleum for Saint Tiburtius (see above), which stood just to the north of the apse of the basilica.
We would have loved to visit the Mausoleum of Saint Helena, but our guide said he had no authority to let us in. The building is apparently administered by the Vatican and the gates are currently kept closed. There have long been plans to turn it into a museum, but as of early 2018 these plans are just that: plans. We decided to admire the mausoleum from a distance and concluded that is impressive. Originally, it must have been at least 25 metres high, but the dome collapsed at an unspecified date in the Middle Ages. As was already mentioned above, Helena’s sarcophagus ended up in the Vatican Museums. The mausoleum was likely stripped of its marble decorations and if there were mosaics – a similar mausoleum for Constantine’s daughters elsewhere in Rome certainly suggests they must have been there – these also disappeared long ago. The remains of the dome are very interesting: amphorae were used in its construction and these are clearly visible. The use of these amphorae was a neat trick to make the structure lighter. It did not prevent the dome from collapsing several centuries later, but this may admittedly have been the result of an earthquake.
The mausoleum now looks a bit silly because a church dedicated to Saints Marcellinus and Peter was built into it in the seventeenth century. This church is now deconsecrated and set to accommodate the museum in the near or distant future. A new church was constructed closer to the Via Casilina in 1922. This church of Santi Marcellino e Pietro ad Duas Lauros is a neo-Romanesque building in soft pink and white (see the image above). It looks charming, but its historical interest is close to zero.