If you want to book a visit to the main museums of Rome (including the Colosseum and archaeological area), the official website to do so is: www.coopculture.it If you want to book a visit to the Vatican museums, the official website for doing so is: www.museivaticani.vaInstead the St. Peter’s Basilica, like all other Catholic churches do not require a ticket but are open to the public, according to a schedule that varies from church to church. Churches can not be visited during religious services.