We have made the last minute decision to spend two nights in Rome so we can visit Vatican City. For the one full day we will be there, we will be in Vatican City all morning, but should have the afternoon and evening to walk around Rome. We're not expecting to take in all of the sights of the city, but perhaps get a gelato or cocktail and take in a little of the atmosphere. Maybe a glimpse of the Coliseum or Trevi Fountain. What area of the city would you recommend that will give us easy travel to Vatican City, but allow us to walk around in the afternoon and see some sights.
We prefer anywhere in the historic center-near Piazza Navonna, Pantheon, Campo de’Fiori
You can walk to the Vatican/St Peter’s from there as well as to ancient sites
How are you arriving and departing Rome? I would probably stay in the Termini area but it would be about an hour hike to the Vatican. But the Termini area gives good access to local transit to the Vatican and elsewhere. Just hop the bus to the Vatican area and then walk back pass the other sites. .
Train from Florence to Rome and we are returning home from Rome by plane..
Personally I would stay in the Termini area -- Hotels Sonya, Aberdeen. Sonya is closer. Just across from the Opera House. Easy to walk to/from Termini and for the L Express to the airport. Good restaurants in the area. It is a bit noisy and lots of people coming and going but handy.
ps. Travel 2015 (below) just reminder me. You must use taxi stands in Rome. You cannot hail a cab in the street as you might in Chicago or New York.
Another vote for the Pantheon/Campo di Fiori area. That is our favorite location for a base in Rome. Easily walkable to both the Vatican and many of the other sites you mentioned. There are a couple of taxi stands in the area and we have never had an issue finding an early ride to the airport in the morning.