Along the axis that crosses the old town centre of Oristano, from the Tower of Mariano to porta Mari, lies one of most famous squares in the town, Piazza Eleonora d'Arborea, in which there is a wealth of important and religious buildings. Around statue of the Giudicessa, you can admire the Church of San Francesco d'Assisi, Palazzo Corrias Carta and, on the corner of Corso Umberto I, Palazzo degli Scolopi. In its place, states the historian Angius, there was one a synagogue, 'justified' by the presence of a substantial Jewish colony that, during Spanish domination, was forced to leave the Island. Other news on the complex dates back to 1536-40, based on reports from the Council meetings that were held here during those years. The building then became the site of the Jesuit convent: the Scolopi, in 1682, opened an institute there, which was financed by a rich merchant. The Piarists occupied the lower floor of the convent and remained active until 1886, the year in which the religious orders were suppressed and replaced by the Regio Ginnasio. Today, the Oristano Town Hall is located here: inside it, there is the council room, with a sandstone entrance portal, and administrative offices.

The complex was renovated in 1830 by Fra' Antonio Cano. This architect and sculptor from Sassari used classical elements on the long, tall façade. He also intervened on the richest monument, the former Church of San Vincenzo, now a council hall: of his work, four statues of the Evangelists still remain and are located in niches on the perimeter walls. During the fascist period, this space was used as a courtroom and the niches were walled over, in order to conceal the symbols of piety, which were not suited to its new function. The hands, which were protruding from the wall, were destroyed. Another typical decoration is the wrought iron balcony overlooking the courtroom. From here, walking along a corridor with arches, you will reach the sala giudicale (judicial room) in which there are two large paintings by Antonio Benini, 'Matrimonio di Donna Eleonora' (Lady Eleonora's Wedding) and 'Proclamazione della Carta De Logu' (Proclamation of the De Logu Legal Code), and a bronze crown donated by the Venetian women in Oristano in honour of Eleonora (1884). Another intervention took place in the mid-19th century, by Gaetano Cima, who designed the other two neoclassical buildings in the square (Palazzo Corrias Carta and the church of San Francesco). The architect from Cagliari tried to create an austere façade, over the previous one, with a Purist imprint: still remaining from this experiment, are the geometric rigour and a search for a compositional rule.