(GMT)20 JAN 2018 NEM2SI:
Suggested route travellers can discover Rome's historic centres on foot in less than 8 hours. This route starts from the train station, Roma Termini, and north towards the Piazza della Repubblica, Piazza di Spagn(the shopping street, Gucci, Prada etc are here), Pantheon, and then, off to the open air art market by the Piazza Navona, Across the Tiber, there’s the Castel Sant’Angelo, a gateway to the city-state of the Vatican and Trastevere(cozy neighborhood in Rome), Rome’s main hub, Piazza Venezia and the ancient masterpiece, Colosseum.
There are many more tourist attractions in Rome but this is likely to be the best suggestion travellers can follow especially who don't have much time to stay in Rome.
Follow the link below for more detailed itinerary. According to the travel blog below it quite depends but travellers would allow 8 hours for this route including short stop and relax at cafes and restaurants......