Two riders and an obelisk

This square sits on the highest of Rome's seven hills, and from here you look out over half the city. The two colossal statues of young men with horses are Roman copies of Greek originals, and in antiquity they stood at the Baths of Constantine, just a little further along.

In the Middle Ages people took them for Castor and Pollux, and the names of their supposed makers, Phidias and Praxiteles, are even carved into the bases, though none of that holds up.

The obelisk between them was added in 1786 and comes from the mausoleum of Augustus, while the basin the water falls into was once a cattle trough on the Forum.

The palace behind it began as the summer residence of the popes, then became the royal palace, and since 1947 it has been the official home of the Italian president. Bernini had a hand in the long wing that runs along the street.

For the view across the rooftops to the dome of St Peter's, the balustrade on the west side is where you want to be.

We take the steps down along Via della Dataria and keep going until we reach the Trevi Fountain, then follow it westward to Piazza di Pietra and on toward the Pantheon quarter.