Dominating Castel Gandolfo's skyline, the 17th-century Palazzo Apostolico was the pope's traditional summer residence. However, since 2016 it has been open to the public and you can now visit the papal apartments and explore the palace's marble halls. Look out for portraits of around 50 popes as well as costumes, robes and assorted Vatican paraphernalia, including the BMW that Pope John Paul II used when he stayed at the palace.
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