The Arborense Antiquarium Museum is located in Oristano . The reason why an archaeological museum was established in Oristano in 1938 lies in the moral legacy of Tharros, boasted by Oristano, which became the seat of the Archbishop and the judge of Arborea in 1070 welcoming the refugees of Tharros.

Since then the people of Oristano transported the spolia, that is the marbles, the columns, the capitals, the square blocks of Tharros from their mother city to build the cathedral, the churches, the monasteries, the palaces and the turreted walls.

In Oristano the most conspicuous collections of Tharrense antiquities had been formed, including those of the judge Francesco Spano, of the nobles Paolo Spano, Salvatore Carta and that of the antiquarian Giovannico Busachi. A part was purchased by the museum of Cagliari, while another part remained in Oristano, where a young lawyer from Sèneghe (OR), Efisio Pischedda (1850-1930), started the constitution of the largest private collection of antiquities in Sardinia.

The Pischedda collection became a reference point for national and international archeology: we can remember the visit of the French prehistoric Émile Cartailhac, of Friedrich Von Duhn, director of the Institut für Klassische Archäologie of the University of Heidelberg, Thomas Ashby director of the British Scholl in Rome , Giovanni Pinza, Giovanni Patroni, Antonio Taramelli and other renowned scholars.

After Pischedda's death, in 1930, the Superintendent of Antiquities and Art of Sardinia, Doro Levi, obtained from the Municipality of Oristano the commitment to purchase the important collection, which constituted the municipal fund of the Antiquarium Arborense since 1938. The current neoclassical seat of the mid-nineteenth century, which belonged to Senator Salvatore Parpaglia, was opened to the public on November 28, 1992.