Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
10,000,000
visitors
How to estimate it
Fermi’s official “Napkin math”
The easiest place to start is how many people visit Rome each year, something like 20 million tourists. How many of them make time for St. Peter's? Plenty spend their days on the Colosseum and the food instead, so call it half, which works out to around 10 million people a year.
- Tourists visiting Rome each year, roughly
- 20,000,000
- Share who make time for St. Peter's
- × 0.5
- ≈ result
- 10,000,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Average daily visitors in a typical (non-Jubilee) year
- ~27,000/day
- Days in a year
- 365
- ≈ result
- 10,000,000
Reference cited by Fermi: Vatican tourism estimates compiled by Italian travel-industry statistics (Statista, religious-site visitor tracking)
How close was your guess?
Your comparison will appear here.
Compare by ratio: divide the larger number by the smaller one. The closer to 1×, the better.