Non fuit in solo Roma peracta die…
Rome was not built in a day…and as well you cannot tour it in a day as well!
So be prepared and before going there make a sort of a wish list of what you want to see, especially if you are short in time. Personally i have visited it few times so I have divided in between “roman classic” and "all the rest " but I have the luxury of reaching it in 3 hours…
So, as a suggestion, consider Circus Maximus, the Imperial Forii, the Coliseum (with visits ) will need approx one day and St. Peter +Vatican Museums and the axis Piazza del Popolo, Piazza Navona, Piazza di Spagna , fontana di Trevi another one (just strolling around !!).
Of course this is just the tip of the iceberg… because you can easily spend weeks in Rome touring around.
Be careful, all visits at the main places have to be booked fairly in advance (weeks ) !!
Two small tips :
if you want to have a special view of the city go the Gianicolo view point , it’s huge!
want to have an alternative way to visit the Vatican Museum? Get the breakfast ticket for the early entrance and enjoy a cappuccino and croissant in the glorious Pigna Courtyard before visiting the Museum or get the Aperitif ticket on Friday!!
