The secret conclave to select a new pope begins on Tuesday, March 12.
Steeped in ritual and prayer the Roman Catholic cardinals are expected to reach a conclusion quickly, taking an average of just over three days in the last nine with none of them going over five days.
Until then the world’s media will have their attention turned on the iconic chimney, for when white smoke appears it is the first signal that there is a new pontiff.
On Tuesday morning the 115 cardinals attend a public mass at St Peter’s Basilica and then, in a tradition dating back to medieval times, they shut themselves into the Vatican’s Sistine Chapel, only to emerge when someone is chosen.
For the moment there is no clear favourite to lead the scandal-ridden church, and the cardinals will have no outside contact until after a decision is reached.
euronews' Simona Volta on the cardinals' arrivals at the Vatican
The Cardinals come in dribs and drabs, some on foot, others in cars to enter the Vatican, smiling for the crowds of reporters, cameramen and photographers that await them. They're confronted with a forest of microphones all trying to steal a last word from the cardinals who now remain hidden to the rest of the world. Enclosed in a conclave that will decide who among them will take the place of Benedict XVI as Pope. When you try to approach them, jostled by the Vatican gendarmerie, the cardinals look at you and seem to want to say "I'm sorry, but I just cannot. My orders are to be silent." Then they offer a touching smile and you suspect that, perhaps, they want to let go and tell you what they're feeling inside. Because it can't be easy to undertake such a decision: a choice that will decide the future of the Catholic Church. And you imagine that maybe some of them would prefer to be a thousand kilometers away from here.
During what is normally the off-season local businesses have received a huge boost.
The Vatican City has been full to the brim with thousands of tourists, pilgrims and journalists who flocked there after two weeks ago Benedict VXI became the first pontiff to step down in almost 600 years.