Technically not a walk, but I certainly encountered it on a walk.
At the edge of Piazza Navona, near Via di Pasquino, you’ll find Fontana del Moro, which features of of my favorite figures in the square: a man wrestling a dolphin.
Giacomo della Porta created the fountain in 1675; Bernini added the Moor in 1673. The other fountains in the square–Fontana dei Quattro Fiumi (Bernini, 1651) and–Fontana del Nettuno (della Porta, 1574) are certainly glorious, but, for me, the Moor’s energy and movement elevate it above the Piazza’s Neptunes and Rivers.
In 1874, a replica statue was installed as the original statue moved to the Galleria Borghese, which is a half hour walk (or seven minute car ride) away from Piazza Navona. Borghese was a major collector of Bernini’s works, so it’s fitting. It’s also a good thing as, in 2011, a 52 year old man was arrested for vandalizing Fontana del Moro as well as Fontana di Trevi with a rock.