In Rome, the churches are legion. Little parishes and great basilicas alike meet travelers on every block of the ancient city, their facades mingling with shops and restaurants, apartments and ancient ruins.  

Although unique visions of beauty and faith greet all those who cross the thresholds of these churches, on the outside precious few stand out, their sheer number often giving architectural wonders the appearance of sameness. For the most part, these churches are simply part of the city’s fabric, woven in as tightly as the government building to the left and the cappuccino bar to the right.  

What’s true above is also true below.

City down below 

Beneath the great basilicas of Rome, beneath the masterpieces of Raphael, Michelangelo and Bernini, are the ruins of temples and domiciles, shops and baths. The same white marble remnants of the pagan past that lie scattered about Rome’s city center also lie buried in the basements of cathedrals. Upon them, the churches were built.  

A journey down into the dark, humid corridors that snake below Rome’s houses of prayer reveal some surprising Christian foundations.  

Consider the Basilica of Sts. John and Paul.  

Originally constructed in the early fifth century, the basilica pays tribute not to the apostles John and Paul, but rather the martyrs John and Paul, saints of the Roman Canon. Today, its interior bears few traces of its paleo-Christian beginnings. But below, it’s a different story. 

There, more than 20 interweaving rooms tell the tale of the church’s origins. 

The tale is a layered one.  

It begins in the second century A.D. when two apartment complexes were constructed near the Roman Forum. Joined by a courtyard, the buildings’ windows afforded the families who dwelt there a bird’s-eye view of military parades and the travels of the great.  

Decades later, in the third century, the lower level of the complex was converted into an arcade of shops.  

Later still, in the early fourth century, Rome’s population waned and the complex was once more restyled, this time into a single, noble dwelling. The home’s first owners are unknown, but eventually two eunuchs of the emperor’s court, the imperial guards John and Paul, took up residence there. 

For a time, they served the emperor and practiced their Christian faith freely. But that changed with the accession of Julian the Apostate. Julian’s reign was short, from 360-363, but not short enough for John and Paul. Someone betrayed their secret, soldiers were sent to their home, and when they refused to worship Julian, they were murdered on the spot.  

Fellow Christians buried the martyrs in the home’s walls. Soon afterward, three of them, Sts. Crispus, Crispinano and Benedetta, were caught praying at the tomb. More martyrs were made, and they too were buried inside the home. Eventually, Christians arranged for the purchase of the building, and under the auspices of the senator Bizante, remodeled the space for worship.  

A few decades later, Bizante’s son Pammachio undertook the building of the great basilica above, using the pillars of the martyrs’ home as his foundation. The rooms beneath and the story they told were forgotten. The martyrs alone were remembered until, in the late 19th century, the Passionist fathers who ran the basilica went exploring. 

Hidden history 

It’s possible they got the idea from the Irish Dominicans, who had done some exploring of their own on the opposite side of the Forum.

In 1857, they went poking around the foundations of the Basilica of St. Clement, discovering not only the original fourth-century basilica, but also another, lower level, which formed the foundation of the first basilica. That basilica was destroyed in 1084 when Norman soldiers sacked the streets of Rome. Rather than restore the original, builders filled in the lower level with rubble and dirt and used its walls as the new building’s foundation. 

Historically, it’s important. From its beginnings as one of the first churches of the newly Christian empire to its more recent history as a shelter for Jewish refugees during World War II, its walls have many stories to tell. But the most interesting stories may lie one level deeper. 

There, archaeologists have uncovered two more ancient buildings, which hint at the reason why the Basilica of St. Clement was built on that spot. The first building appears to have been the home of a wealthy Roman family, built shortly after Nero set fire to Rome, in A.D. 64. Later, the home’s owners donated it to pagan worshippers.  

There’s always something appropriate about building a Catholic church over a pagan temple, but the real reason for the location of the Basilica of St. Clement may have more to do with the adjacent building, which was at first thought to be a government building.  

But later research turned up evidence of a much different history. That evidence suggests that a wealthy Christian named Clement bought the property from Nero and there built an office for his freed slave, a Jewish convert to Christianity. That slave had taken his former master’s name, and now shepherded the Church as its fourth pope: St. Clement. In short, the building upon which the Basilica of St. Clement was built may have been nothing less than the first Vatican.  

Vatican treasure 

The modern-day Vatican has an underground story of its own, a story of buildings and bones uncovered at the height of World War II.  

At the same time Pope Pius XII was hiding Jews in the Basilica of St. Clement, he also commissioned digging beneath the main altar of St. Peter’s. There, archaeologists found narrow streets paved with brick and lined with mausoleums. It was a necropolis, a long forgotten burial ground of ancient Rome hidden from view since the early fourth century, when Constantine, needing flat ground upon which to construct the first Basilica of St. Peter, razed the hill upon which the mausoleums sat. 

It had to be that hill, of course, because Christian tradition held that St. Peter was crucified and buried there. Instead of an elaborate mausoleum, his resting place was a humble hole in the ground, marked at first by the hidden tributes of Christians, then later by a small marble monument, the Trophy of Gaius.  

Above that Trophy, Constantine was said to have placed his basilica’s altar. And in that same spot, more than a millennium later, Bernini too placed his altar.  

Some believed the stories. Others thought them pious legends. But when Pope Pius XII’s archaeologists went exploring, they found the Trophy of Gaius right where it was supposed to be, directly under the main altar of St. Peter’s Basilica. They also found a wall covered in early Christian graffiti, marked again and again with one name: Peter. Most importantly, they found, wrapped in an ancient purple cloth, what likely are the skeletal remains of the fisherman pope.  

Each of these underground worlds through which privileged pilgrims now pass, shed light on a different aspect of early Christian history. But each in its own way tells the same story, a story of a faith so vibrant, beautiful and true that it permeated the very stones of a wayward world.  

And in that, they not only have a story to tell, but also a reminder to give. They remind all Christians that it’s not enough to have penetrated the past. The faith must also penetrate the present. It must penetrate what lies all around its churches — the streets and shops, offices and souls of the post-modern world. It happened once before. And with grace, it can happen again. 

Emily Stimpson is an OSV contributing editor.