Bernini’s Fountain of the Four Rivers in the Piazza Navona. Come early in the morning or very late at night to get the best experience of it, without the crowds. If you stop by at sunset, take a look and then head over to the nearby roof of the Hotel Raphael for a cocktail, http://www.rapahelhotel.com
And there’s this one in the Piazza Santa Maria in Trastevere. Stop by the Caffe di Marzio to admire the scene–always colorful, whether morning or night. Eat nearby at D’Augusto (15 Piazza da Renzi), for classic Roman pastas at budget prices.
It’s dreamy to be walking by this one…
On the Via Giulia, behind the Palazzo Farnese. Those expert Renaissance partiers, the Farnese, would fill it with wine for their celebrations.
Here’s another Bernini, The Turtle Fountain in the Jewish Ghetto at Piazza Campitelli. Stop by on your way to one of the most romantic restaurants in Rome, Vecchia Roma, http://www.ristorantevecchiaroma.com.