The north-western portion of the island, called the Nurra, lies to the west of Sassari and to the north of Alghero, and is entirely volcanic; so are the mountains to the south of it, near the west coast; the highest point is the Monte Ferru (3448 ft.).
The Mesozoic beds are limited in extent, the most extensive areas lying around the Gulf of Orosei on the east and west of Sassari in the north.
The mean winter temperature for Sassari for1871-1900was 48° F., the mean summer temperature 73° F., while the mean of the extremes reached in each direction were 99° F.
1 in., and in that of Sassari 21.99%, the percentage for ten provinces of south Italy being 24.35.
The cultivation of the vine prevails far more in the province of Cagliari than in that of Sassari, considerable progress having been made both in the extent of land under cultivation and in the ratio of produce to area.