? Two days before Heart of Italy tour in September ?

Helpful to others if you post a link to the tour so we can see what is included

https://www.ricksteves.com/tours/italy/heart-italy-2024

That tour does take you to Vatican and Colosseum

I would recommend a food tour
EatingEurope Trastevere or Testaccio tours both get rave reviews ( I can vouch for Trastevere am tour)
EATWELL10 should still work for a discount

https://www.eatingeurope.com/rome/

And
Visit the Borghese Gallery IMO a must see and one of the best museums in all of Europe
Must pre book your entry
It’s limited to a 2 hour visit so very easy to fit in
They sell out quickly

Official ticket site
https://www.tosc.it/artist/galleria-borghese/galleria-borghese-2253937/

ETA:
Ooops my mistake
Vatican and Sistine not included as noted by Kathy, so that could be your priority

Hi kansasrod!
Oh my gosh, there are so many interesting things to see in Rome! before diving into long list of what those many things are, may I ask what sorts of things might most interest you? For instance, there is wonderful art museum in Rome that I can highly recommend if you enjoy art. It's not huge and can easily be seen in the 2-hour time slot you'd book for.

As well, I see that the tour doesn't visit the Vatican Museums/Sistine chapel. That one is a VERY busy place that tends to be very crowded but is high on many visitors' gotta-do lists.

Churches! Rome is FULL of them, they're all a little (or a lot) different, and most of 'em are free. As well, many of them can be considered museums of valuable sculpture or other types of artwork so are real budget-stretching bargains. Some of them are also very old and built upon even earlier churches, Roman basilicas or temples. I don't think I've met one yet I didn't find interesting! LOL, ask my DH: I've dragged him through several dozen of them so far. :O)

And then there's the other really, really old stuff: the Baths of Caracalla; the catacombs out on the Appia Antica (highly recommend seeing at least one); a walk by the crumbling remains of tombs, an emperor's private circus snd some other stuff along the Appia itself, Portico di Ottavia in the Jewish Ghetto area....

So what trips your particular trigger? What can you tell us about yourselves that'll help us to help you?

2 sites that I enjoy in Rome are not on the usual tourist map. On one of my trips I went out to see the ancient aquaducts. At the time, I couldn't find a tour and went via public transportation. However I googled it today and found at least 2 tours that now go to the Aquaduct Park. They are a magnificent example of Roman engineering. In Rome, I always visit Torre Argentina, a 6 minute walk from The Pantheon. It is in the middle of large square, it is an undeveloped site of ancient monuments, but it is also a cat sanctuary. And, it is where Julius Caesar was assassinated. I love to watch the cats walking around and sunning themselves on the ancient ruins.

Hi there, well the choices in Rome are pretty endless, but not being sure of your interests, the Capitoline Museum is a good choice for ancient history, sculptures & mosaics. I would book tickets in advance directly, and note the tourist office where you pick up the tickets is a ways down the street, so don't climb all those stairs without first getting tickets! Apparently late afternoon is quieter so may not need advance booking then, but my feet would complain if I tried to do 2 museums in the same day. There's a fabulous view out overlooking the Forum, and a coffee shop on the top floor of museum, described in my Dec TR here, along with some good restaurant and casual pizza spots for a quick bite. https://community.ricksteves.com/travel-forum/trip-reports/rome-was-jammed-over-ny-but-still-fun.
I know RS no longer goes into the Sistine Chapel & Vatican Museums, "only" St Peters in the morning, I see from your tour. If you're absolutely willing to tolerate wall to wall people, noise & intense crowds, you could book this for afternoon, but get suggestions on where to eat beforehand, or eat inside museum.

Your hotel is close to Roma Termini train station, so if you love ancient art, my first choice would be to start with Palazzo Massimo, just across the street from the station. It's filled with ancient frescos, mosaics, Roman & Greek statues and is an under-visited gem! We saw about 5 people there in 3 hours & 14E ticket price includes the Diocletian baths across the street and a few other museums as well. You could see this museum in the morning, take a taxi to Trevi Fountain and go explore the very unique Vicus Caprarius, the underground museum / aquaduct that flows into the fountain. You DO need to book via Whatapp the day before, we lucked out arriving around noon, it opens at 11AM, & were given a time slot 1.5 hours later, so we had time for pizza lunch, our fav pizza this visit at “Pizza In Trevi", very simple has some tables and you order as you enter. Also discussed in TR.

Or if you need a break from the city, maybe an e-bike tour along the Aurelian walls, with or without the catacombs? Also in the TR above, we took taxis to see the Museum of the Walls, enchanting way to get out of downtown. Hope you have a great time!!

PS, ChristineH is absolutely right, I too would recommend a food tour -
EatingEurope Trastevere or Testaccio tours both get rave reviews ( I can vouch for Trastevere am tour). And I can vouch for the Testaccio morning tour, off the beaten track! I forget about the Borghese, having had the luxury of going there a few times, I would put it ahead of the Capitoline Museum, if you're interested in Baroque sculpture! Yes, it has gilded ceilings & Caravaggio paintings but the sculptures were FABULOUS. PS, wear hiking boots!! Your feet will ache on all the Roman cobblestones. And BTW, I adore Voltera, your first night in Tuscan, excellent less crowded choice on RS's part.

Another suggestion
The tour starts with the RS Heart of Rome walk in the evening-past lit up fountains etc

We like to do that walk in both directions—once in am, once in pm
You could just walk! Start at Campo dei’Fiore for the market and end at Piazza del Popolo for lunch -(then maybe head up the hill to the Borghese-or pick up picnic fixings along your way and eat lunch in the Borghese park
Pop into any church you pass-make sure you have knees and shoulders covered!

Rome is a living history museum
No matter what you decide to do you’ll be amazed
Hope you love it as much as we do!

Thank you one and all. Especially advice about Capitoline Museum tickets; Palazzo Massimo; Borghese Gallery; repeating walk in opposite direction — we are Volkswalkers so walking is good!