Big picture: Explore St Peter's Square
Thousands of people are expected in St Peter's Square in Rome over the next few days, eager to find out who will be the next Pope. They are watching for white smoke to billow from a chimney on the roof of the Sistine Chapel indicating that a final decision has been reached. Explore the image below to find out more about what is going on while the cardinals deliberate.
One of the 140 statues of saints on the colonnades around the square. St Bruno founded the religious Carthusian Order in 1084. Members spend most of their lives in silence and solitude, they do not eat meat and fast once a week. St Bruno went on to become an adviser to Pope Blessed Urban II.
St Martha's House
This is where the cardinals come to stay when they are not taking part in the conclave. It was built in 1996 to provide housing for those with business at the Vatican. As well as the cardinals, priests from the regular clergy will stay here for the duration of the conclave, to hear confessions. There will also be two doctors and cooking and cleaning staff.
The Swiss guard stand at the entrance to Vatican City. The guards have protected the Pope since 1506, when Julius II first hired Swiss mercenaries for his personal protection. There are guards on duty every day at all the main entrances within the Vatican and they are also responsible for maintaining order when the Pope is in public. They are all trained marksmen.
This mobile post office is selling rare "Sede Vacante" stamps in the square. The stamps are only sold when there is no Pope - 150,000 were snapped up in the first week of sales.
St Peter's Basilica
All 115 voting cardinals attended the final mass in the basilica before the selection process began. The dean of the College of Cardinals, Cardinal Angelo Sodano, called for unity within the church. After the service the cardinals filed into the Sistine Chapel to begin the selection process.
These three tourists managed to get prime position in the front row, directly opposite the balcony where the new Pope will make his first public appearance. They saw the black smoke showing no decision had been reached - but they had not decided whether they would stay until the new Pope was finally chosen.
After the final mass, cardinals processed in order of seniority into the Sistine Chapel. Once inside they had to swear an oath of secrecy, then everyone else was ordered out before the doors were closed. All the voting takes place here, from the second day, two ballots are held in the morning and two in the afternoon. The ballot papers are then burned, giving off the smoke visible to onlookers outside. It traditionally turns from black to white once the new Pope has been chosen.
Big screens are strategically placed around the square and transmit live pictures of the chimney on the Sistine Chapel, when the results of a vote are expected. The smoke only appears twice a day, after the second vote in the morning, and again in the afternoon.
The Knights of Malta, a sovereign Catholic order, have an agreement to supply volunteers to help the Vatican Hospital provide first aid in the square. As many as 90,000 pilgrims are expected to pass through the square during and after the papal election, so 92 Knights of Malta volunteers are on hand to provide assistance with everything from cuts, bruises and dehydration to heart attacks.
Watch below for live coverage of the specially installed chimney on the roof of the Sistine Chapel in the Vatican.
The smoke, which is visible to onlookers in the square, traditionally turns from black to white once a new pope has been chosen.