Rome Underground Temples Tour: Crucifixion Relics & San Clemente
Descend beneath the Colosseum to touch an underground river and walk where early Christians worshipped in hiding.
This walking tour of Rome takes you through the Basilica of San Clemente, where you descend three layers underground to see a preserved Temple of Mithras and touch the river flowing below the city streets, then visit four churches: the Basilica of St. John Lateran, the Holy Stairs, and the Basilica of the Holy Cross in Jerusalem: to see original Crucifixion relics including a nail from the cross, wood of the cross itself, and thorns from the crown of thorns. A live guide in your chosen language leads groups of no more than ten people. Entrance fees and headsets are included. The itinerary adapts if any church areas close, keeping the overall duration the same. Dress code requires knees and shoulders covered. Moderate walking fitness is needed, and the tour is not wheelchair-accessible.
Step-by-step itinerary
- Basilica of San ClementeEntry included1h 15m
- Basilica of St. John Lateran30m
- Holy Stairs15m
- Basilica of the Holy Cross in Jerusalem30m
- Rome TerminiEntry included1h
Explore underground temples and churches
- Visit underground St. Clement's Basilica
- See Temple of Mithras and underground river
- Walk to Basilica of St. John Lateran
- Learn about Emperor Constantine and early Christianity
- Visit the Holy Stairs
- Explore Basilica of the Holy Cross in Jerusalem
- See Crucifixion relics and nativity fragments
- Optionally visit Basilica of Saint Mary Major
The experience
What makes San Clemente different from other Rome churches is what lies beneath it. You descend through three distinct layers: a medieval basilica on top, a fourth-century Christian church in the middle, and a first-century Roman house with a Temple of Mithras at the bottom. Your guide walks you through the progression from pagan worship to early Christian practice, showing you mosaics that survived centuries underground and letting you touch the actual underground river that still flows beneath the Colosseum. The group stays small, capped at ten people, so you're not navigating tight underground passages in a crowd.
From there you walk to the Basilica of St. John Lateran, Rome's cathedral, to learn why it's called the "Mother and head of all churches on Earth" and hear how Emperor Constantine's decision to legalize Christianity in 313 changed everything. The golden interior and ancient frescoes frame the story of the early persecutions and the martyrs who came before that shift. Then you climb the Holy Stairs: the actual stone steps Jesus walked at his trial in Jerusalem, brought to Rome by St. Helena, Constantine's mother, after her pilgrimage to the Holy Land. You finish at the Basilica of the Holy Cross in Jerusalem, built with soil brought from Jerusalem itself, where the relics are kept: a nail from the Crucifixion, the wood of the cross, the board Pontius Pilate placed above it, thorns from the crown of thorns, and fragments from the cave of the nativity in Bethlehem.
Your guide speaks English, Spanish, Portuguese, Italian, or one of two other languages, and headsets let you hear clearly even in echoing stone spaces. The tour runs 2.5 to 3.5 hours depending on which version you book: some options include a fifth church, the Basilica of Saint Mary Major, with its mosaics and additional sacred relics. If any church area is closed on the day you visit, your guide adapts the route to alternative sites without changing the total time. Wear comfortable walking shoes and clothes that cover your knees and shoulders. Public transportation stops are nearby if you need them.
What’s included
- Live professional guide in your chosen language.
- entrance fees to all churches and the underground sections of San Clemente.
- headsets so you can hear your guide clearly in echoing spaces.
- groups limited to a maximum of ten people.
Options for this experience
16 optionsSee 13 more options
Information
Lasts 2h 30m–3h 30m, runs every day at 09:00, 12:00 and 15:00, from € 75 per person, with live guides in 6 languages, in groups of up to 10 and with free cancellation up to 24 h before.
Prices and times updated today
Operated by TOURIKS
Is this one for you?Book the shared option if you're comfortable exploring with other travelers and want the lower price. Choose private if you prefer the guide's full attention and the flexibility to linger at any stop. Either way, the small group size, never more than ten, means you're not jostling through tight underground passages or crowded basilicas with dozens of others.
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Top questions
What languages is the tour guided in?
In English, at 09:00, 12:00 and 15:00. In Spanish, French, German, Italian and Portuguese, at 09:00 and 15:00.
Can children come?
Yes. Ticket types: Child (7 to 16 years); Infant (under 7): free.
What happens if it rains?
It may be canceled due to bad weather. If that happens, you're offered another date or a refund. Free cancellation up to 24 h before the start.
What exactly is the Temple of Mithras, and why is it underground at San Clemente?
The Temple of Mithras is a first-century Roman shrine to a god worshipped across the empire before Christianity spread. It sits at the lowest level of San Clemente because later Christians built their church directly on top of the Roman house that contained it, and then a medieval basilica was built above that: three layers of history stacked on each other over centuries.
Are the Crucifixion relics at the Basilica of the Holy Cross in Jerusalem authentic?
The Basilica of the Holy Cross in Jerusalem houses relics that St. Helena, Constantine's mother, brought back from her pilgrimage to Jerusalem in the fourth century, including a nail from the Crucifixion, wood from the cross, the board Pontius Pilate placed above it, and thorns from the crown of thorns. The church itself was built with soil brought from the Holy Land to preserve them.
How much walking is involved, and will I be comfortable in the underground sections?
The tour involves a moderate amount of walking across four or five churches and down into the underground layers of San Clemente. The underground passages at San Clemente are navigable but tight. The tour is not wheelchair-accessible, and it's not recommended for people with claustrophobia. Comfortable walking shoes are essential.
What should I wear to visit these churches?
An appropriate dress code is required: knees and shoulders must be covered. Plan accordingly, especially if you're visiting in warm weather, since you'll be inside stone basilicas for the entire tour.
What happens if one of the churches is closed when I visit?
If any church area is closed due to maintenance, liturgical events, or other reasons, your guide will adapt the itinerary to highlight alternative sites. The overall duration of the tour remains the same.
Rome Underground Temples Tour: Crucifixion Relics & San Clemente
2h 30m–3h 30m · EN · ES · FR · DE · IT · PT
from € 75 per person
≈ US$ 86 in your currency