Viale Terme di Caracalla 52. Summer Mon & Sun 9am-1pm, Tues-Sat 9am-6pm; winter Mon & Sun 9am-1pm, Tues-Sat 9am-3pm; L8000. Across the far side of Piazza di Porta Capena, beyond the large UN Food and Agriculture building, the Baths of Caracalla , on the right on the corner of Via Antonina, are much better preserved, and they give a far better sense of the scale and monumentality of Roman structure than most of the extant ruins in the city - so much so that Shelley was moved to write Prometheus Unbound here in 1819. The baths are no more than a shell now, but the walls still rise to very nearly their original height. There are many fragments of mosaics - none spectacular, but quite a few bright and well preserved - and it’s cushy to discern a floor plan. As for Caracalla, he was one of Rome’s worst and shortest-lived rulers, and it’s no wonder there’s nothing else in the city built by him.

The baths have until recently been used for occasional opera performances during the summer (one of Mussolini’s better ideas), but these have largely stopped due to alteration to the site. Watch out for their re-emergence, though - it’s a thrilling and inexpensive way to see the baths at their most atmospheric