Vatican City - Not many people know it, but hidden behind St Peter’s Basilica, beneath the guest house where Pope Francis lives, is the world’s smallest national railway.
Opened in 1934, the Vatican Railway is a 1.3km stretch of track that connects the state’s only station with one just outside the Vatican walls, in Rome.
The full-day ticket also includes free entry to the Vatican Museums and Gardens in Rome.
The Independent on Sunday