The Romans built the Appian Way straight as a ruler across the Campagna, but when it reached the Alban Hills, the old volcanic massif south-east of Rome, even they had to bend a little. At Ariccia, the road crossed a deep valley on a huge viaduct of stone blocks, parts of which still survive, and climbed past Albano and Genzano toward Velletri and the south.
The Alban Hills are the Castelli Romani, a ring of hill towns where Roman nobles and later popes built summer villas to escape the heat of the city. Castel Gandolfo, overlooking the crater lake of Albano, was the summer residence of the popes for centuries. In Ariccia, Bernini designed the main square and church, and the modern bridge across the valley offers dramatic views. The town is famous for porchetta, whole roast pork with herbs, sold in fraschette, simple taverns where you eat it with bread and local white wine.
Nearby, Lake Nemi, a smaller crater lake, was where the emperor Caligula kept two enormous ceremonial ships, recovered in the 1930s and later destroyed by fire during the Second World War. Nemi is also known for its tiny wild strawberries. Genzano holds the Infiorata, when the main street is carpeted with flower petals in elaborate designs.
For riders, the Castelli Romani offer winding roads through chestnut woods, vineyards and olive groves, with views over the lakes and the Roman plain. The roads can be busy, especially at weekends, when Romans flock to the hills, and town centres are narrow, with traffic restrictions. The SS7, the modern Via Appia, runs through Albano and Ariccia, and is a busy main road. Fuel and food are easy to find. Come on a weekday morning, ride around the crater rims, and stop for porchetta at lunch.