Grottoes vs. Necropolis: What’s the Difference?

The grottoes: free with basilica entry

The Grottoes are the burial crypts directly beneath the floor of St. Peter’s Basilica. They hold the tombs of popes, most visibly John XXIII in a glass-sided case. They are free to enter with your basilica ticket. You can walk through on your own, though the €20 guided tour provides context and skip-the-line access.

The Grottoes sit between the basilica floor and the Scavi street below. When you descend the Grottoes, you are entering a crypt; when you descend further (on a separate, much harder-to-book tour), you reach the Scavi.

The Scavi: the 2nd–4th-century mausoleum street

Below the Grottoes lies the Scavi — the 2nd–4th-century pagan-and-Christian mausoleum street where Constantine’s builders buried the old necropolis when they levelled the hillside to build the first basilica. It runs directly beneath the basilica floor, constant ~20°C, humid, narrow, and ancient. Groups of 12, 90 minutes, ending at Peter’s grave. €13, booked direct with the Ufficio Scavi, 2+ weeks notice, min. age 15.

The vertical stack

Picture it this way:
— Basilica floor (where you walk when visiting the church)
— Grottoes (papal-tomb crypt, one level down, free with entry)
— Scavi (2nd–4th-century mausoleum street, two levels down, €13 direct)

Most visitors who see a “Vatican necropolis” tour see the Grottoes. To see the actual Scavi (the older, more evocative necropolis), you must book the official Scavi tour months ahead direct with the Excavations Office.

What a tour includes

€20 Grottoes tour: You see the Grottoes level, the papal tombs, some historical context. You do NOT go deeper to the Scavi mausoleum street.
€33 dome + underground tour: Includes Grottoes access and a brief underground section, but not the full Scavi archaeological site.
€54 dome + papal tombs tour: The most popular option — Grottoes, dome climb, live guide, 10,212 reviews. Still not the full Scavi.
€13 Scavi tour: The only tour that descends to the full 2nd–4th-century mausoleum street and ends at Peter’s grave. Booked direct, 2+ weeks, min. age 15.

Frequently asked questions