Sassari is the second-largest city in Sardinia in terms of dimensions and the number of inhabitants (circa 120.000) and it is the main city of the province. The historical centre is characterised by cobblestone streets, arches, underpasses and small piazzas which are dominated by splendid old buildings. The old part of the town was protected by the surrounding wall, started in the 13th century by the Pisans, continued by the Genoese and modified by the Aragonese.

The Aragonese Castle was built in 1330, after the building of the wall; it was later demolished in 1877 so that the Lamarmora barracks could be built.

Sassari maintained the typical aspect of medieval city until halfway through the 1800s, when the process of urban expansion forced it to renounce the defensive wall, of which much evidence remains to this day.

Amongst the various monuments that can be visited one may note:

- The Cathedral of San Nicola , 12th century;

- Church of the Trinità (1640);

- The church and cloister of Santa Maria di Betlem , 13th century;

- Corso Vittorio Emanuele II , the main street of the historical town, with many shops and elegant old buildings;

- the graceful fontana di Rosello , built by Genoese artists in 1606;

- Piazza d'Italia , built in 1872, it occupies a surface area of 1 hectare and is surrounded by several old buildings in the Liberty style. It is overlooked by Palazzo Giordano, in Neogothic style, and the beautiful Palazzo della Provincia , built in 1880 in the neoclassical style.

- the Palazzo Ducale, which is the seat of the Town Hall , the building of the University of Sassari , built between 1611 and 1651, the palazzi of the umbertino period (19th century).