The body of former Pope Benedict XVI will be laid to rest on Thursday in the tombs beneath the Basilica.
He died on New Year’s Eve at the age of 95, almost a decade after he stood down because of ill health.
Pope Francis will preside over Thursday’s funeral – the first time a Pope will be buried by his successor.
The funeral will take place in St Peter’s Square.
The last papal funeral, that of Pope John Paul II in 2005, was one of the largest Christian gatherings in history, and drew an estimated four million people to Rome.
Benedict asked that the funeral be marked by simplicity, Vatican spokesman Matteo Bruni told journalists.
Details of the guest list have not been released, but the Vatican has said that it will include delegations from Italy and Benedict’s native Germany.
