AP

Pope Francis, left, and Pope emeritus Benedict XVI pray together in Castel Gandolfo Saturday, in this photo provided by the Vatican paper L'Osservatore Romano.

Pope Francis and his predecessor Benedict prayed together before having lunch in a historic meeting Saturday.

The new pontiff flew to the papal residence at Castel Gandolfo in the Alban Hills outside of Rome by helicopter Saturday. Pope Benedict XVI has been living there since he resigned Feb. 28, becoming the first pope to step down in 600 years.

Both men wore white papal outfits.

Father Federico Lombardi, a Vatican spokesman, said that Benedict and Francis had embraced at the helipad, then went to a private chapel to pray.

Benedict, who looked frail and walked with a cane, told Francis to kneel in front of the altar, but Francis said, "let's kneel together" and they did so, Lombardi said.

"We're brothers," Francis reportedly told the former pope as the two prayed together on the same prie dieu.

They then had a private conversation for about 40 minutes in the library, before going to lunch.

Francis presented Benedict with a gift of an icon of the Virgin Mary.

“When I saw this picture of the Madonna of Humility, my thoughts turned immediately to you,” Francis told his predecessor, according to Eurovision News.

The Associated Press reported that crowds gathered near then villa in the hope of catching a glimpse of history.

The news agency speculated about what the two men would discuss:

The two popes might discuss the big issues facing the church: The rise of secularism in the world, the drop in priestly vocations in Europe, the competition that the Catholic Church faces in Latin America and Africa from evangelical Pentecostal movements.

They might also discuss pressing issues concerning Francis' new job: Benedict left a host of unfinished business on Francis' plate, including the outcome of a top-secret investigation into the leaks of papal documents last year.

Francis might want to sound Benedict out on his ideas for management changes in the Holy See administration, a priority given the complete dysfunctional government he has inherited.

They might also discuss the future of Monsignor Georg Gaenswein, Benedict's trusted aide who has had the difficult task of escorting his old pope into retirement and then returning to the Vatican to serve his successor.

Gaenswein has appeared visibly upset and withdrawn at times as he has been by Francis' side. The Vatican has said Francis' primary secretary will be Monsignor Alfred Xuereb, who had been the No. 2 secretary under Benedict.

NBC News' Ian Johnston and The Associated Press contributed to this report.

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This story was originally published on Sat Mar 23, 2013 7:56 AM EDT

Alessandro Di Meo / EPA

A garden at the Apostolic Palace of Castel Gandolfo, the pope's summer residence, on the outskirts of Rome. Pope Benedict XVI officially steps down on Thursday, Feb. 28. Benedict will stay at Castel Gandolfo until renovations on his permanent home are completed. Click the image for more photos.

Even though Pope Benedict XVI is leaving the papacy, he'll remain in sumptuous, familiar surroundings — at least for a few weeks.

Sometime in April, Benedict will take up permanent residence in Mater Ecclesiae, a modest convent for cloistered nuns at the Vatican. The convent is under renovation, however, so in the meantime, Benedict will live at Castel Gandolfo, the small town of about 8,000 people a few miles southeast of Rome that has been the summer retreat for popes for almost four centuries.

Vatican records indicate that Benedict has spent an average of five weeks a year at the grand Apostolic Palace at Castel Gandolfo since he assumed the papacy in 2005, so he should feel quite at home.

Alessandro Di Meo / EPA

A light switch bears the Papal seal.

And what a home it is. The complex, which overlooks Lake Albano and what's left of the enormous villa of the first-century Roman Emperor Domitian, actually dwarfs Vatican City by almost 400,000 square feet. It comes complete with landscaped gardens, an arboretum, natural conservatories, museums and fish ponds.

Step inside Pope Benedict's temporary new home

The sculptured gardens, which make up more than half of the estate, are a favorite retreat for popes, who have been known to frequently take long walk along their paths. 

And don't forget the 25 dairy cattle, which are reputed to produce some of the finest milk in Europe.

The town is named for the castle of the Gandolfi family of Genoa, which was built around 1200. It was originally a fortress against marauders, which explains its high walls and other ancient barriers. 

Franco Origlia / Getty Images

The Apostolic Palace and the Pontifical Villas of Castel Gandolfo on Lake Albano will be the Pope Benedict XVI's residence during the next Conclave, in Rome, Italy. The Apostolic Palace of Castel Gandolfo, 10 miles south Rome, is also the summer residence for popes.

Formally speaking, the Vatican assumed control of Castel Gandolfo only in 1929 under the Lateran Treaty, which formalized relations between Italy and the independent state of Vatican City. But in reality, it has been the church's domain since 1596, when Pope Clement VIII seized it from the Savelli family in lieu of unpaid debts, according to the Vatican's official history.

Today, it's home not only to the Apostolic Palace but also the Vatican Observatory (where visitors can see a moon rock collected during the Apollo XVII mission), the Villa Barberini (where many remains of Domitian's palace are still visible), Villa Cybo (which is used by school of the Maestre Pie Filippini religious community), apartments for 21 employees and the Pontifical Church of St. Thomas of Villanova.

The spectacular view of Lake Albano from the complex has inspired many artists. Landscapes of the scene by Jean-Baptiste Camille Corot, J.M.W. Turner and Claude Lorraine, among others, hang in some of the world's premier museums.

The complex itself is the setting for stunning works of religious art, as well, among them frescoes by Jan Henryk de Rosen and Angelo Righetti's statue "Madonna of the Park."

The Pontifical Church, designed in 1658 by Gian Lorenzo Bernini, the leading sculptor of his age, features interior domes and statues by Antonio Raggi, famous for grand pieces such as the "Virgin and Child" in Paris and the marble "Death of Saint Cecelia" in Rome. One of Bernini's own masterpieces, a fontana, or fountain, adorns the the piazza facing the Apostolic Palace.

At Castel Gandolfo, "I find everything: a mountain, a lake; I even see the sea," Benedict remarked in 2011. Those words are now engraved on a plaque in the town hall.

Benedict will move in to Castel Gandolfo late Thursday afternoon. He'll get there by helicopter — a tradition started in 1975 by Pope Paul VI, who wanted to avoid traffic on the ancient Appian Way.

Paul VI was an especially enthusiastic visitor to Castel Gandolfo. In 1972, he described its charms in words that might resonate with Benedict, who said he was abdicating because of his age and declining health:

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A view of a grotto inside the pope's summer residence.

"We, too, enjoy this God-given gift, by breathing the fresh air, admiring the beauty of our natural surroundings, appreciating the enchantment of its light and silence and seeking here to restore our lack of energy, which is never enough and now even a little scarce."

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