In Vatican City, a city of astounding churches, St Peter’s Basilica outdazzles them all. Awe-inspiringly huge, rich and spectacular, it’s a monument to centuries of artistic genius. On a busy day, around 20,000 visitors pass through here. If you want to be one of them, remember to dress appropriately – no shorts, miniskirts or bare shoulders. If you want to hire an audioguide (€5), they’re available at a desk in the cloakroom to the right of the entrance. Free English-language guided tours of the basilica are run from the Vatican tourist office, the Centro Servizi Pellegrini e Turisti, at 9.45am on Tuesday and Thursday and at 2.15pm every afternoon between Monday and Friday.