San Giovanni in Laterano
The Pope's own cathedral — older than St Peter's, and far less visited.
Why it matters
San Giovanni in Laterano is the cathedral of the Bishop of Rome — meaning it technically outranks St Peter's in the Catholic hierarchy, despite receiving a fraction of the visitors. Founded in the 4th century, it's the oldest Christian basilica in Rome.
What to see
The Baroque interior was redesigned by Borromini in the 17th century. The adjacent Lateran Baptistery is the oldest baptistery in the Western world, and the Scala Santa — said to be the stairs Jesus climbed at his trial — draws pilgrims who ascend on their knees.
Getting there
Metro line A to San Giovanni, or a short walk from the Colosseum area — easy to add to the same half-day as the Baths of Caracalla.
Technically outside Italy
As one of the Vatican's four extraterritorial papal basilicas, San Giovanni in Laterano is legally Vatican property despite standing well outside Vatican City's walls — a quirk of the 1929 Lateran Treaty that most visitors walking through the piazza have no reason to know.
The Holy Stairs next door
Adjacent to the basilica, the Scala Santa (Holy Stairs) are believed by tradition to be the staircase Christ climbed during his trial in Jerusalem, brought to Rome by St Helena — pilgrims still climb the 28 marble steps on their knees as an act of devotion, a striking sight for visitors unfamiliar with the practice.
The Rome Index