The City Underneath
A vertical walk through Rome on and around the Celian hill, where a single church can hold three cities at once and the older, stranger town is usually still down there, holding everything up.
4.41|100 minutes|3.6 km|6 Stops
Start
Basilica di San Clemente: The Three-Layer Section
1
Basilica di San Clemente: The Three-Layer Section
A twelfth-century basilica standing on a fourth-century church standing on first-century Roman streets, the single clearest place in the city to see time stacked floor by floor.
2
Basilica dei Santi Giovanni e Paolo al Celio: The Hidden Houses
A lived-in basilica on the Celian hill whose depth is invisible from the nave, sitting on about twenty decorated Roman rooms rediscovered only in the nineteenth century.
3
Colosseo: The Amphitheatre on the Drained Lake
Read from the street as the top layer over a vanished landscape, a public monument raised on a filled-in imperial lake in the grounds of a lost golden palace.
4
Arco di Costantino: The Collage of Older Emperors
A triumphal arch that is itself a layered object, assembled with reused sculpture lifted from monuments of earlier emperors to link a new ruler to Rome's past.
5
Basilica di San Giovanni in Laterano: The First Center
After one long deliberate leg east, the cathedral of Rome and seat of the pope, the oldest of the four major papal basilicas and the only church titled an archbasilica.
6
Scala Sancta e Sancta Sanctorum: The Room That Outlived Its Palace
The closing beat across the piazza, twenty-eight marble steps and a single surviving papal chapel that anchored the story after the medieval palace around it was rebuilt away.
Best Time to Visit
Early morning or the last hours before closing, when the churches are quiet and the low light softens the cobbles. Aim to reach San Clemente near opening to have the layers to yourself, and try to cross to the Lateran before the midday heat settles over the open piazza. Weekday mornings are calmer than weekends, and shoulder-season months spare you both the peak crowds and the worst of the summer sun.
Pro Tips
- •Wear shoes you trust on worn stone and shallow steps, because the underground levels and the ancient lanes like the Clivo di Scauro are uneven and dim.
- •The upper churches are free to enter, but the buried levels are ticketed and often need booking ahead: San Clemente's excavations require online pre-booking, so reserve before you set out if you want to go down.
- •Carry a little cash in small coins for the modest chapel and cloister fees, since the Sancta Sanctorum, the Lateran cloister, and the Case Romane charge only a few euro each.
- •Bring a refillable water bottle and top it up at Rome's public drinking fountains, especially before the longer, more exposed leg east to the Lateran.
- •Keep shoulders and knees covered so you are never turned away at a church door, and pack a light layer, because the underground rooms stay cool even in high summer.
- •Go at your own pace and skip freely: the stops stand on their own, so linger where the buried floors pull at you and move quickly past what does not.
Safety & Precautions
- Watch your belongings closely around the Colosseum, the Arch of Constantine, and the Lateran piazza, where crowds are dense and pickpockets work the busiest tourist zones; keep bags zipped and in front of you.
- Mind your footing throughout: cobblestones, ancient street surfaces, and the narrow stairs down into the excavated levels are uneven and can be slippery, so take the descents slowly.
- Respect church dress codes by covering shoulders and knees, and keep your voice low and phone quiet inside active places of worship where services may be underway.
- Plan around the midday heat in warmer months by carrying water and seeking shade, and remember that ticketed underground sites like San Clemente's excavations may sell out, so book ahead rather than counting on entry at the door.
Gallery
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