Liberation Day

I've never been to Rome in late April, so I don't know what conditions will be like then. The usual guidance is to avoid free-entry days at very popular sights. It's a good time to go to secondary attractions.

St. Peter's is always a popular sight, and if you just walk up, there will be a very long security line. Entrance to St. Peter's is free, but I'd recommend booking an entry time (modest cost) so you can use the shorter security line for those with entries. That entry includes an audio guide.

In case you are not aware, the Sistine Chapel is not in St. Peter's; it's part of the Vatican Museums. Except for the morning of the last Sunday of the month (April 26), there is an entry fee for the Vatican Museums. Tickets sell out well in advance, and you should expect massive crowds. See https://www.museivaticani.va/content/museivaticani/en.html. At this point there are only late-afternoon regular-entry tickets available on April 25 and only tour tickets available on April 26. The Vatican Museums are large, so I'd want an earlier entry, but pickings are slim at this point. Commercial tours--at a much higher cost--may be available earlier in the day on April 25.

Think like Italians think. The trick is understanding that if you do not work on Saturdays and Sundays, you may ask your employer a four days holiday (27-28-29-30) and enjoy actual holidays from April 25th to May 3rd, that is 9 days. This is what a lot of Italians will do - in Italian it is called a "ponte", that is a bridge between festivities, this year the trick is that May 1st (Labor day) is a Friday, near a Saturday, and this is why I would expect the whole week to be crowded.

The holiday itself is not a big deal. Generally on that day there are some Antifascist rallies organized by the ANPI (National Association Partisans of Italy) in some piazzas and venues of major cities. They are peaceful rallies with music and other fun events, I think many State museums are free on that day (probably not the Vatican Museum, which is in another country). Due to the confluence of two major holidays around that time, Liberation Day on April 25, and the much bigger Europe-wide Labor Day in May 1, many people take advantage of the nice weather to take the whole week off and flood major tourist destinations, like Rome, Florence, Venice, etc. the biggest problem I’ve had during that week anywhere, not only in Rome, but also Cinque Terre, Paris, etc.is finding accommodations, because crowds are big. So reserve your hotel, if you haven’t already.