Papal Palace of Castel Gandolfo historical timeline

What a visitor stands in front of at Castel Gandolfo is a building that has changed job four times. A thirteenth-century castle became papal property in settlement of a debt, Carlo Maderno turned it into a summer palace for Urban VIII, the popes stopped coming for sixty years over a territorial dispute with Italy, and in 2016 the palace became a museum -- opened, crucially, without a single structural change. That omission is why it could be handed back: from July 2026 it is the pope's summer residence again, and the Vatican Museums publish a calendar of closures to say when.

Chronology

1. 81-96 The emperor Domitian has a residence on this ground. The papal gardens occupy its site, so the terracing and the outlook over Lake Albano were an imperial choice first.
2. 1200s A castle is built here, the building the Vatican would later acquire.
3. 1596 The Vatican acquires the castle in payment of a debt owed by the Savelli family. It enters the papal estate as a bad debt rather than a purchase.
4. 1626 Urban VIII begins using the palace that Carlo Maderno -- the architect who completed St Peter's -- designed for him, in the spring. About half of his successors have used the properties as a summer residence since.
5. 1870-1929 In dispute with Italy over territorial claims, the popes do not leave Vatican City at all, and the summer palace stands unused for two generations.
6. 1929 The Lateran Treaty makes the palace, and the Villa Barberini that Pius XI added to the complex, extraterritorial properties of the Holy See: Italian territory, papal ownership, exempt from Italian taxes and expropriation, closed to Italian authorities without consent.
7. 1934 Pius XI, having had the facilities modernised, begins using the retreat again after the sixty-year gap.
8. 1944 An unknown number of Jewish refugees shelter at the palace under the protection of the Holy See, and many people use the site as a refuge from the Allied bombing raids -- more than 500 dying in one such attack. The extraterritorial line was real protection and it was not absolute.
9. 1958 Pius XII dies at the palace.
10. 1978 Paul VI dies at the palace, the second pope to do so in twenty years. John Paul II later has a swimming pool built here, which draws criticism and photographers.
11. 2013 Benedict XVI flies here at the conclusion of his papacy on 28 February, is joined by Francis for lunch on 23 March, and returns to Vatican City on 2 May. In June Francis announces he will not spend the summer here, and on 7 December names Osvaldo Gianoli Director of the Pontifical Villas.
12. 2014 The Vatican opens the Barberini Gardens to paid visitors on escorted tours in the mornings, every day but Sunday. They are still visited that way.
13. 2015 A public train service from Vatican City to Castel Gandolfo begins on 11 September, on a train previously reserved for the pope. Before the end of the year the estate's farm produce, until then available only to Vatican employees, goes on public sale, and Benedict takes a two-week holiday here at Francis's invitation.
14. 2016 The palace itself is opened to the public for viewing on 21 October, without undergoing any structural changes. Castel Gandolfo's mayor expects the conversion to be hard to reverse.
15. 2025 A communiqué of the Prefecture of the Pontifical Household on 17 June restores the palace's status as a place of papal residency, and from 6 July Leo XIV begins a six-week stay -- though in the Villa Barberini, the main building still being a museum.
16. 2026 Security problems at the Villa Barberini settle it. Minor renovations from May make the official palace habitable, and from 5 July Leo XIV stays in the main building -- the sixteenth pope to summer in the official papal summer residence, and the reason the Museums now publish closure dates.

Survival and restoration

The decisive conservation decision here was made in 2016 and it was a decision not to act. When the palace was opened to the public for viewing on 21 October that year, it was opened without undergoing any structural changes. The mayor of Castel Gandolfo thought that made the museum permanent -- "the fact that the palace is now a museum will make a reversal in the future difficult" -- and the opposite turned out to be true. Because nothing had been cut into the building to display it, minor renovations beginning in May 2026 were enough to make it habitable again, and a decade of museum use ended without loss.

The real damage to this estate came from the air. Allied bombing raids in 1944 killed more than 500 people in a single attack on a site people were using as a refuge, under a Holy See protection that had also sheltered an unknown number of Jewish refugees. The complex itself survived to carry on as a papal retreat.

The other long interruption was political rather than physical: between 1870 and 1929 the popes did not leave Vatican City, so the palace stood unused for sixty years until Pius XI modernised it and resumed using it in 1934. Protection since has been legal as much as physical -- extraterritoriality under the Lateran Treaty, exemption from Italian taxes and expropriation, and a prohibition on Italian authorities entering without the Holy See's consent.

• Wikipedia