In the center of the city the ancient town building or "Arengario" is substantially intact. It dates of the end of the XIII century, with parvis, beautiful bifores (windows with 2 lights) and trifores (windows with 3 lights) and a square tower. In the inside it is preserved archaeological and artistic material.

Not far there is the Cathedral, Duomo the main monument of the city, devoted to Giovanni Battista. It was founded in 595 by the Longobard queen Teodolinda, but it was almost entirely reconstructed in the XIII and XIV century, and its inside was later changed and decorated during the XVI and XVII century. The marmoreal façade was completed from 1350 to 1390 by Matteo da Campione: it has bands of white and green marbles, enriched by a magnificent rose-window and adorned of a beautiful portal. On the side of the Cathedral there is the bell tower of 1606. In the inside there is the Chapel of Teodolinda (Longobard queen), adorned of frescos of her life made by the brothers Zavattari (1444). The altar contains the famous "Corona Ferrea" (iron crown): its name came from the legend according to which it has been forged with a nail of Jesus Christ's cross, afterwards dressed of gold and stormed of gems (V-VIII century). With the "Corona Ferrea" many kings were crowned starting from the Middle Ages (also Napoleon, May 26th 1805, in the cathedral of Milan). Together with the "Corona Ferrea", a rich treasure is preserved in the Cathedral of Monza.

The Villa Reale is composed of neoclassic style buildings; it was built in 1777-80 thanks to the archduke Ferdinand of Austria from the project of Giovanni Piermarini. Today it hosts the Civic gallery of art and the historical Museum with cloths of the XVII century and works of the XIX century. Inside the Villa there is the Royal Library that has been realized around 1893 by the architect Majnoni. The huge number of volumes in its shelves was dispersed beginning from 1901; in fact in the April of that year all the books of the Regina Margherita were sent to Rome and at the end of 1919 a "smaller number" (about a thousand of them!) were sent to the other royal residences of Villa Savoja in Rome and the Castle of Recconigi.