Earth : Europe : Italy : Central Italy : Lazio : Castelli Romani
The area of the Castelli is volcanic. The former crater is occupied by two lakes, Albano and Nemi. As the area’s altitude is higher than that of Rome the richer Romans used to frequent it for its fresher climate during summer. This tradition was followed by the Popes, who still have their summer residence at Castel Gandolfo. The area is well-known for its wine, particularly that of Frascati although with a few honourable exceptions the quality is not too high. Ariccia is celebrated for its porchetta (roasted pork meat), while Nemi is a berry fruit center. A wide range of mushrooms can also be found in the Castelli.
Several of the towns of the Castelli are connected with Termini station in Rome. There are two lines: one goes to Frascati while the other connects Rome with Marino, Castel Gandolfo and Albano.
The Castelli is also conveniently reached from Ciampino airport (see Rome) now used by a number of the budget airlines like Ryanair  and EasyJet . However, you may have trouble finding a taxi willing to take you in the opposite direction to Rome.
The area is easily reached by car. Avoid Sundays between April and September as the area becomes crowded. Leave Rome on the Via Appia Nuova or the Via Tuscolana. If you take the Appia turn left at the end of the Ciampino Airport runway and follow the Via dei Laghi (Road of the Lakes). You will pass Marino on your left and eventually find Lake Albano on your right. Beware that several of the higher Castelli towns have narrow winding roads that are difficult to drive in for the inexperienced.
There are bus services, but your ability to see all of the Castelli area in one day will be rather limited.