The International Summer School on Historic Masonry Structures 2025 will take place in the old town of Oristano. 
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Oristano is located on the central-western coast of Sardinia, facing the gulf of the same name, at the mouth of the Tirso river.
The territory of Oristano has been inhabited by man since the pre-Nuragic and Nuragic periods. In the 8th century BC, as part of the Phoenician colonization of the coast, the cities of Tharros -in the territory of Cabras- and Othoca -in the territory of Santa Giusta- arose.
Aristianis, built near the ancient Phoenician-Punic and Roman city of Othoca, became an important center in 1070, when the Archbishop of Arborea Theoto moved the bishopric there, abandoning the now decayed city of Tharros, and the Judge Orzocco I  erected it as the capital of the Giudicato of Arborea. Judges were “kings” of the Arborea kingdom (Giudicato di Arborea). The transfer of the capital of the kingdom from Tharros to Oristano was propelled by the Saracen incursions that raged on the western Sardinian coast in those years, and to which the city of Tharros was subject.

The “Giudicati Sardi” were independent state entities that had power in Sardinia between the 9th and 15th centuries. Their political and administrative organization mimicked the typical structure of the territories of the Byzantine Empire, with Roman-Byzantine legal institutions.
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