Know Before You Go
Visiting the necropolis can only be done through an advanced reservation. Requests must be made in writing and groups are limited to 12 people, all of which must be 15 years of age or over.
The excavation site can be quite hot even in winter as it is humidity-controlled to preserve the structures. Keep this in mind when choosing what to wear for the day, as you’ll likely want to dress in layers but will still need to comply with the dress code for visiting a holy site (shoulders covered, women in pants or skirts below the knee.)
The entrance is very difficult to find, walk around the outside of St Peter’s square. You’re looking for the Swiss Guard up the border path on the outside of The Vatican on the left side if you’re facing the Basilica steps, not the Swiss Guard posted at the Arco del Campane. You’ll need to have your papers printed and in hand to get through the security checkpoint.