The old town and city centre are walkable. The main sights — the cathedral, the Fontana del Rosello, the Museo Sanna, and Piazza d'Italia — are within easy walking distance of each other.
For day trips to Alghero, Porto Torres, Castelsardo, and Santa Trinita di Saccargia, a car is the most practical option. Car hire is available from Alghero airport, which is the usual entry point. Buses (ARST) connect Sassari to the main towns of northern Sardinia, but services are infrequent and slow by Italian standards.
A small urban train network — the trenino — connects the city centre to some outer neighbourhoods, but it's rarely useful for visitors.