May 1, in Rome

Walk! There is so much to see and experience without going into any building. It could be your best day in Rome . . . certainly your cheapest.

Several museums are open as well as most churches. The Borghese Gallery and the Castel Sant’Angelo are open as are several other tourist sites.

Here's an excerpt of a post I made back in January - the context was a suggested itinerary for someone with just one day in Rome:

You could walk through the Jewish Ghetto, using the walk in the Rick Steves Rome guidebook as a template, but I would extend it to walk through the ruins behind the Teatro Di Marcello, which is similar to what you would experience at the Forum, albeit on a much smaller scale.

From there it's an easy walk to the Victor Emmanuel monument. To the right of it is the Michelangelo Grand Staircase, which will take you up to the Piazza del Campidoglio. If you head to the rear, between the buildings that comprise the Capitoline Museums, you'll find two overlooks with great views of the Roman Forum - no ticket required.

Those views, along with a stroll down Via Del Fori Imperiali past the Imperial Forums toward the Colosseum, may give you enough of a view of ruins so that you wouldn't need to spend more time going inside the Forum and Palatine Hill.

Another easy view of ruins is at Largo Argentina - while the ruins can be viewed from the sidewalk, it's now open as a tourist site, when you can buy an inexpensive ticket and descend to the level of what's left of the ancient temples.

It's not necessary to purchase a single admission ticket to enjoy much of what Rome has to offer - at any hour of any day.

I was there May 1 a few years back. All the churches were open, and many museums (look ahead at the museum hours to be sure). You should have plenty to do and see.