Frascati is the most visited of the Castelli Romani hill towns, perched in the Alban Hills about 20 kilometres south-east of Rome. It has been a retreat from the city heat since ancient times — the Romans called the area Tusculanum — and the legacy is a string of Renaissance and Baroque villas with extraordinary gardens. Today it is best known for its white wine, Frascati DOC, which you can drink directly from the source.
The heart of town is Piazza Marconi, with long views down across the Roman plain. From here it is a short walk to the Duomo, to Villa Aldobrandini (the most spectacular of the hillside villas, designed by Giacomo della Porta in 1598), and to the backstreet fraschette where locals still fill demijohns from the barrel. The Porta Porticella market is a good spot to pick up bread, cheese, and cured meats for a picnic.
The best time to visit is during the Sagra dell'Uva in October, when the town celebrates the grape harvest with processions, free wine flowing through a fountain on the piazza, and general good cheer. But Frascati is worth a trip any time — it is an easy and very pleasant half-day from Rome by train.