The adage, when in Rome, do as the Romans do, sounds easy enough, if you consider building the Colosseum, a comprehensive system of roads and aqueducts, conquering almost the entire Mediterranean world, and laying the foundations of Western civilisation to be easy. The accomplishments of the ancient Romans were truly astounding, even based on what we already know, and new discoveries are being made every day… some beneath the city itself!

A Lost Roman Neighbourhood Found Beneath a New Subway

In 2023, workers building a new subway station at the Piazza Venezia made a startling discovery. A multi-story complex from the 2nd to 1st centuries BCE, a working-class neighbourhood from the ancient world, lying beneath the streets of modern Rome. According to archaeologists, the buildings likely contained homes and shops of Imperial Rome’s working class. The complex in question would have been standing during the age of Julius Caesar and Augustus. The location is a short walk from the Forum and the Pantheon. Over centuries of building and redevelopment, later streets and palaces gradually buried the neighbourhood.

A Hidden Army Barracks Discovered Under a Modern Station

The same construction project that ran into the aforementioned ruins under the Piazza Venezia stumbled upon another discovery much earlier in the project. In November 2016, workers unearthed a nearly 10,000 square foot building from the Hadrian period (around the 2nd century CE). Sleeping peacefully beneath the modern Roman streets was a 2,000-year-old army barracks! Thought to have belonged to the elite Praetorian guard, the secret service of ancient Rome, the barracks consist of 39 rooms, complete with mosaic floors and frescoed walls. The find was made all the more chilling with the discovery of a mass grave containing 13 adult bodies entombed with several brass artefacts.

A Military Commander’s House Lies Dormant Beneath the Streets for 2,000 Years

It seems as if you just can not dig a hole in Italy without finding some Roman ruins. Two years after discovering the army barracks, workers on the same Metro C line that excavated the former subterranean finds dug up the home (or Domus) of the Praetorian guard commander attached to the barracks ruins previously found. The Domus contains at least 13 rooms featuring white and black tiled geometric designs and frescoed walls, replete with a courtyard and crumbling fountain. The first find of its type in the city, the numerous ruins discovered while constructing the Metro C line, will be used to turn the subway stations into mini-museums that commuters can enjoy along their travels.

The Gladiator School Hidden in the Shadows of the Colosseum

Construction workers in 1937 happened upon one of the most fascinating archaeological sites from the ancient Roman Empire. Beginning formal excavations in the late 1950s and ’60s, archaeologists unearthed the ancient Roman gladiator school, Ludus Magnus. The greatest of the empire’s four known gladiator training schools, it is situated directly to the east of the colosseum and features a secret tunnel that would bring gladiators into the heart of the arena. Boasting a large courtyard for training and mock battles, and also a small arena with seating for 3,000, evidently gladiatorial combat had its own pre-season of sorts. With comprehensive kitchen, bath, and medical facilities, in addition to a large dormitory-style living quarters, the school was the last place many Roman warriors lived before meeting their fate (and possibly lions) in the ancient world’s most blood-soaked arena.

A Secret Tunnel City Lurks Beneath Capitoline Hill

Since the days of Julius Caesar, a network of tunnels has existed under the famed Capitoline Hill. Used variously as a quarry, cistern, tavern, subterranean marketplace, and WWII bomb shelter, Italian dictator Benito Mussolini sealed the network of tunnels in the 1920s. Covering over 42,000 square feet, the vast underground complex is only steps away from the forum. The little-known city of tunnels has been closed for over a century, but that is only a blip in the 2,000-year-old history of the subterranean passageways. An expensive restoration project is currently underway, and the secret tunnel city will open for visitors in the near future.

The Cult of Mithras Hides Under a 12th-Century Church

The Basilica of San Clemente is already a must-see spot for tourists, pilgrims, and art historians visiting the Eternal City. With stunning mosaic floors, the Basilica is one of the most richly adorned churches in all of Rome. Underneath the famed 12th-century Basilica are layers of construction that take visitors on a below-ground tour through the history of the holy city. One layer below the church lies a church from the 4th century that boasts some of the finest medieval frescoes in the world. As you descend deeper into the history of the city, the next layer is a temple of the cult of Mithras, created in the late 2nd century CE within a 1st-century Roman building. Although the mithraeum is the deepest level that can be visited, the whole complex is built upon the foundation of a nobleman’s home that likely burned during the fire of 64 CE.

The Site of Caesar’s Assassination Concealed Below a Public Square

Discovered during a public works project in the early 20th century, the Largo di Torre Argentina concealed four Republican era temples and Pompey’s theatre, the site of the assassination of Rome’s most famous statesman, Julius Caesar. The temples were dedicated to pre-Christian deities such as Juturna, Fortuna Huiusce Diei, Feronia, and Lares Permarini. A fascinating look at ancient Roman religion, the four temples date to the time before the empire, when Rome was a republic. In fact, the site of Caesar’s assassination marks the moment Rome began to transform from a republic to an empire.

No trip to Rome is complete without visiting some of these sites from the ancient Roman underground. The city beneath the city features ancient temples, military bases, hidden churches, artwork, and the school where gladiators learned their deadly trade. Found under modern construction projects and long-hampered attempts to expand the holy city’s subway system, the sleeping history of Rome waits under the streets. What other shocking discoveries are hidden beneath the streets? Only time will tell.