2nd Time In Rome

I would take a daytrip to Frascati on one of your days.

Go to the Aventine Hill for the "Keyhole" view of the Vatican, visit Santa Sabina Church with carved wooden doors from the 4th Century, continue down the path to the little park with a view of the city, then the rose garden as you descend toward Viale Aventino.

Go to the Jewish Ghetto for a few hours, get off the main street and wander down the side streets.

Sometimes there are special exhibitions at Cinecitta, on the metro line.

Other churches: San Clemente, San Luigi dei Francesi.

Trastevere.

On a recent return trip to Rome, we especially enjoyed the Taste of Testaccio tour with Eating Italy. Not only was this a very fun and delicious tour, but it gave us some blessed relief from the hoards in the main tourist areas. It's one of our favorite memories from Rome.

We did a wine dinner with Eating Italy which was quite good.

As for sights, if you haven't been to San Clemente (the underground excavations) then you should do that.

If you didn't do it before, consider a day trip to Ostia Antica or Orvieto.

Consider doing one of the eatwith.com dinners, in the home of a local Roman. We particularly enjoyed the one by Federica and Barbara in Trastevere.

If you'll be there over a weekend, consider Domus Area (Nero's home). They have a virtual reality tour on weekends that is supposed to be spectacular. But its very popular, so I would buy tickets ahead. We just were in Rome and enjoyed our visit to the Aquaduct Park, close to the Cinecitta metro.

I'm loving these suggestions and bookmarking everything that I can. We have loved food tours in other cities, so I'm not sure why I didn't think of a food tour in Rome! :)

Take a pasta class with Walks of Italy - great fun and delicious food!

Or splurge and sign up for Vespa tours with Scooteroma. I hate motorcycles, but I loved this experience. When in Rome...

Not exactly unknown, but I have found Castel S'Antangelo to be very underrated. A lot of people walk right past it on their way to more high profile sights. I only made it inside on my third trip to Rome, and visited again on my fourth trip this past October. There is a very pleasant café with great views on the top level. For me the Keats-Shelley House is also a great, lightly visited sight. I guess you would have to have some interest in English literature to enjoy it though. I also went to the non-Catholic Cemetery to visit the graves of Keats and Shelley, a peaceful and well kept cemetery. There are many churches that are worth a look inside in the Centro Storico area. I wish that I had researched this before my fall 2016 trip.

We won't be making our first trip to Rome until May, but one of the "must sees" for us, and definitely qualifying as "off the beaten path", is the Crypt of the Capuchins (https://en.wikipedia.org/wiki/Capuchin_Crypt), not far from the Spanish Steps.

We spent a lot of time in the Trastevere neighborhood on our last trip. Also, check out Old Bridge gelato - across the street from where people line up to get into the Vatican museum. The piazza del Popolo is one of our favorites - as the name suggests, it is a Roman piazza on a human scale. We also liked the Castel Sant'Angelo, if only for the great view of Rome from the top. The Campo de Fiori is a great place to hang out.

We are planning our second trip to Rome this summer so I've really enjoyed reading all the suggestions! This time we plan to go to the Borghese Gallery (missed it the first time), would like to spend more time in Trastevere, and are thinking about daytrips to Orvieto and Ostia Antica. I love the idea of doing a food tour or a eatwith.com dinner.

If you have not taken the elevator to the top of The Victor Emmanuel monument (near the Forum area)
you can do that. It is a fabulous view of Rome and the 7 hills. You can spend as much time up there as you need. I took lots of photos too. On a clear day it is amazing.

Have you been to Le Domus Romane di Plazzo Velentini? It is an well-preserved house that you tour using a multimedia show on how this one family may have lived. There are limited spots so you need to book in advance, but we really enjoyed this.
www.palazzovelentini.it

There is also the Forum of Augustus light show at night that is a neat experience.

We are also in Rome for the 2nd Time and in looking to do more exploring we have decided to do two Walks of Italy tours, one called Crypts, Bones and Catacombs for some underground exploring and another called "Hidden gems and ancient wonders" which will take us to The Jewish Ghetto and to Appian Way, two places we have been wanting to see. I am also visiting Castle St Angelo and doing the Eating Italy Twilight Trastevere Tour (again!).

Seconding recommendations to visit aqueduct park in Rome (particularly if you enjoy photography, it is a stunningly evocative location, very beautiful and peaceful) and the Castel St'Angelo. The Castel offers many layers of history, it is fascinating. Also has a great view over Rome from the top.