Side Trip to Campo Flegrei (The Phlegrean Fields) ★★

On this seaside peninsula just west of Naples, volcanic vents steam and hiss (the name is from the Greek, “Burning Fields”), ruined villas testify to ancient hedonism, and mythic characters and oracles seem to spring to life. Moonlike landscapes interspersed with lush hillsides carpeted with olive groves and orange and lemon orchards are rich in history and have long evoked colorful storytelling. Our alphabet was invented here, when the Latin language officially adopted the characters used for written communication in Cuma and have come to comprise what’s known as the Roman alphabet. Nero murdered his mother, the ambitious and villainous Agrippina, outside Baia, the Palm Beach of the ancient world, where Caesar relaxed and Hadrian breathed his last.

Getting There

A day exploring this strange, mythic landscape begins in seaside Pozzuoli, reached from Naples by Line 2 of the Metropolitana (subway) or via the Cumana Railroad (tel. 800-053939), starting from Piazza Montesanto. From Pozzuoli, SEPSA buses run to other nearby sights: Baia, Cumae, Solfatara, and Lago d’Averno (www.sepsa.it; tel. 081-7354965). Pozzuoli -- More than 40,000 spectators could squeeze into the Anfiteatro Flavio, built in the last part of the 1st century and the third largest arena in the Roman world. Much of the seating remains intact, as do the subterranean staging areas with “mechanics” that hoisted wild beasts up to the field of slaughter and pumped water to flood the arena for mock naval battles (Via Nicola Terracciano 75; tel. 081-5266007); admission 4€; Wed–Mon 9am–1 hour before sunset). Screen legend Sophia Loren was born in this seaside town in 1934, contributing another bit of local color.

Solfatara -- The ancients called this dormant volcano just 2km (1 1/4 miles) above Pouzzoli “Forum Vulcani” and believed it be the residence of the god Vulcan and an entrance to Hades. It’s easy to see why: lunar landscapes hiss, steam, bubble, and spew sulfurous clouds that reach a temperature of 160[dg]C (320[dg]F). Despite all the bubbling and steaming, the volcano has not erupted since 1198. (Via Solfatara 161, Pouzzoli; www.solfatara.it; tel. 081-5262341; 6€; daily 8:30am to 1 hr. before sunset.)

Baia -- Most of the villas and thermal baths are underwater, though enough remains on terra firma to suggest the grandeur of this ancient spa town where Julius Caesar, Nero, and other Roman elite once relaxed and debauched. Seneca the Younger called the place a “vortex of luxury” and a “harbor of vice.” It was here that Caligula supposedly had a bridge fashioned from a string of boats and road across it on his horse, defying the oracle’s prediction that he had “no more chance of becoming emperor than of riding a horse across the Gulf of Baiae” (http://cir.campania.beniculturali.it; tel. 081-8687592; admission 4€; Tues–Sun 9am to 1 hr. before sunset). The evocative 16th-century Castello di Baia shows off statuary and other artifacts from the ancient city (http://cir.campania.beniculturali.it; (tel) 081-5233797; admission 4€; Tues–Sun 9am–2:30pm).

Lago d’Averno -- This placid lake just north of Baia fills an extinct volcanic crater—and if legends have any truth to them, was once so vaporously lethal that the name comes from a Greek word meaning “without birds,” because winged creatures flying over the waters would plunge to their deaths. The Cumaean Sibyl is said to have ferried Aeneas, son of Aphrodite, across the lake, where he discovered the River Styx, the Gateway to Hades. In the 1st century b.c., Agrippa had a canal dug to connect the lake with the sea, providing safe harbor for Roman ships. A couple of centuries later the Romans built the lakeside Temple of Apollo, a huge thermal complex covered with a dome almost as large, but not as long lasting, as the one on the Pantheon in Rome.

The Greeks founded nearby Cumae, their first colony on mainland Italy, in the 8th century b.c., and they discovered they had a helpful neighbor: the Cumaean Sibyl, who, according to legend, passed on messages from Apollo. A little less poetically, the sibyl’s long, narrow trapezoidal tunnel was probably gouged from the rock as part of the colony’s defense system. The cave is in an archaeological park that also includes temples dedicated to Jupiter and Apollo, later converted into Christian churches (cir.campania.beniculturali.it/archeocuma; (tel) 081-8543060; admission 2.50€; daily 9am to 1 hr. before sunset). On Via Domitiana, to the east of Cumae, you’ll pass the Arco Felice, an arch about 20m (64 ft.) high, built by Emperor Domitian in the 1st century.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.