Vatican workers hoisted a chimney onto the roof of the Sistine Chapel on Saturday in readiness for the conclave of Roman Catholic cardinals that will elect a successor to Pope Benedict.
The conclave begins on Tuesday, with the sequestered cardinals using the chimney to tell the outside world whether or not they have chosen a new leader - black smoke signifying no decision and white smoke announcing a new pontiff.
The rust-colored pipe was attached above the terracotta tiles of the roof of the frescoed chapel clearly visible from the nearby St. Peter's Square, where traditionally thousands of believers gather to see how the secret balloting is progressing.
Although no clear favorites have emerged to take the helm of the troubled 1.2-billion-member Church, the conclave is expected to be wrapped up within just a few days.
No conclave has lasted than more than five days in the past century, with many finishing within two or three days. Pope Benedict was elected within barely 24 hours in 2005 after just four rounds of voting.
Benedict triggered the election last month with his shock decision to abdicate because of his increasingly frail health - the first pontiff to step down in six centuries.
He leaves his successor a sea of troubles - including seemingly never-ending sex abuse scandals, rivalry and strife inside the Vatican bureaucracy, a shortage of priests and a rise of secularism in its European strongholds.
Inside the chapel, workmen were carrying out the final preparations to make the room, one of the most famous in the world, ready for the conclave.
Two stoves were installed and attached to a single flue leading up to the roof. One, made of cast iron and used in every conclave since 1939, will be used to burn ballots.
The second stove is an electronic one with a key, a red start button and seven tiny temperature indicator lights. Flares will be electronically ignited inside it to send out either white or black smoke.
Workmen on Saturday were also putting the finishing touches to specially built rows of tables where the cardinals will sit facing each under the gaze of Jesus in Michelangelo's massive Last Judgment panel on the wall behind the altar.
Nearly 150 red-hatted cardinals held a sixth day of preliminary meetings, known as "general congregations", on Saturday to discuss the many challenges besieging their Church and to sketch the ideal profile of the next pope.
Some 115 of their number - all those aged under 80 - will enter the Sistine Chapel on Tuesday to start the formal voting process. One ballot will be held on the first day, with four votes a day thereafter until one of their number receives a two-thirds majority, or 77 votes.
The names of several possible front runners have been mentioned by church officials ever since Benedict's resignation.
Amongst the most mentioned are Italy's Angelo Scola, Brazil's Odilo Pedro Scherer and Canada's Marc Ouellet. U.S. cardinals such as Timothy Dolan or Sean O'Malley have also been cited as "papabile".
With the vast majority of Catholics now living outside Europe, there is growing pressure for a pontiff from another part of the world.
Many Vatican observers believe a Latin American, Asian or African pope could bring attention to the poverty of the southern hemisphere in the same way the Polish-born John Paul put a spotlight on the East-West divide.
"I think it is important to have someone who comes from a place where the Church is dynamic and lively," South Africa Cardinal Wilfrid Fox Napier told La Stampa newspaper in an interview published on Saturday.
"I believe the choice of candidates will be much longer than it was in 2005," added Napier, who has himself been tipped in some quarters as a possible pontiff.