The rooms where for over five centuries the popes spent their summer holidays, the areas that for centuries were closed to the public, the places where the popes met Sovereigns and Heads of State, are today accessible to the general public.

The Palace of Castel Gandolfo has resisted the damage of the invading Napoleonic militias who were quartered there, and also during World War II when, with the arrival of the Allies in 1944, the surrounding Alban Hills became a battlefield with the German occupation. During this time, Pius XII opened the Palace as refuge to the local population. He also left his own private apartment, including his sleeping area, available to refugees. On the papa bed refugee expectant mothers were accommodated to give birth and forty children were born there, and consequentially called by all "the children of the Pope".

Entering the private papal chapel, here the newly elected Pope Francis meet with emeritus pope Benedict XVI to gather together in prayer.