Also known as the Palazzo della Ragione, this building is one of the city’s iconic landmarks. Its name—Trecento, meaning “three hundred”—refers to the 300 members of the city’s Great Council, composed of both nobles and common citizens, for whom the palace served as a meeting place.

Built in 1185 in the Romanesque style, with a ground-floor portico, the structure underwent various architectural and functional changes over the centuries. It has served as a city court, the governor’s residence, and even a commercial center with dozens of shops and a venue for public assemblies.

The upper floor houses a large hall in the Venetian style, adorned with frescoes from the 14th and 15th centuries. Today, in addition to serving as the seat of the city council, the palace also hosts various exhibitions.