A small and charming town in the province of Frosinone, Guarcino arose in the VIII century B.C. with the name of "Vercenum", inhabited by Ernici (an ancient Italic population), situated in a strategic position, from where it was possible to control the entire Aniene Valley. After the fall of the Roman Empire, the town experienced the destructive fury of the invasions of the Saracens and of the Hungarians. In the Middle Ages, once incorporated into the Papal States, the town established a solid and lasting tie with Rome, especially during the pontificates of Innocent III and Boniface VIII.
The center is flanked by the massive of Campocatino, with peaks at over 2000 meters above sea level, from where it is possible to admire the beautiful landscape of the Southern Lazio region, down to the Tyrrhenian Sea, including the Pontine Islands. The Campocatino area also houses one of the oldest and most popular ski resorts in Central Italy.

Sites of Interest:
- the XVIII century Collegiate Church of San Nicola, with stucco decorations and late Baroque style. It houses several important XVIII century paintings, a fine wooden ceiling in the sacristy, a superb pulpit and a carved choir of the canons with an important Episcopal chair;
- the Church of San Michele Arcangelo, built on the ruins of the pagan temple dedicated to Mars. It is flanked by an interesting sail shaped Bell Tower, unique of its kind in the region. Inside are preserved XIII century frescoes in the crypt;
- Palazzo Patrasso, adjacent to the Church of San Michele Arcangelo, and today seat of the State Archive;
- the old Courthouse, whose impressive façade is dominated by two Gothic doorways and a series of mullioned windows of the same style;
- the Arch of Patrasso, with above, the House the Cardinal;
- Palazzo Tomassi Palace, built in the second half of the XIII century by Cardinal Tomassi, a parent of Pope Boniface VIII;
- the picturesque Old Town center with its narrow streets, squares and noble palaces, adorned with stone portals, capitals and double arched windows.