After leaving the inhabited center of Selargius and traversing a few km of unpaved road, toward Sestu, you arrive at the local rural of Santa Rosa. In one of the territories in the area, there is a small olives park, an archeological site, and a small church built in recent times.
According to recent archival research, since 1350 an Ecclesia Sante Rose de Sextu paid tithing to the Apostolic Camera. Another testimony of its existence is found in the script Triumpho de los santos del Reyno de Cerdeña, where the seventeenth – century author Dionigi reports the existence “antiguamente” of one “Yglesia de S.Rosa” of which only the foundations remained. After centuries of oblivion, in 1946 a group of faithful believers from Selargius decided to build a church dedicated to Santa Rosa, precisely in the place where according to tradition stood in the past. However, it remains uncertain which Santa Rosa considering that there are at least three Santa Rosa mentioned in the sources: Santa Rosa da Lima, Franciscan tertiary Santa Rosa from Viterbo and Santa Rosa martyr sulcitana. The last of the three is the most accredited by scholars. The first stone of the modern church was laid on July 21st in the same year as reported by Canon, Felice Putzu. However, the work stopped shortly after and resumed only in 2012 as part of an area redevelopment project. During the excavation of the foundation two coins were found, one of Valentino III (435-455 AC) and the other of Trasamundo (496-523 AC), useful signs of the last period in the area in ancient times.
The building has a single nave with a Latin cross plan; on the facade, there is a portal with a round arch surmounted by a circular window and a bell tower.
The interior is characterized by a wooden walkway, which leads from the entrance to the apse, built to allow you to observe some of the find found during the excavations (it also built outside the building). These discoveries have revealed several finds belonging to different eras and in particular to the late Punic era (III century BC), the Roman-Republican period (II century BC) and the low medieval period (XIII- XIV century AC). Among them, one that is particularly interesting is a bell shape cistern, of uncertain data, made of sandstone covered with earthenware. The cistern is filled with three different layers that shows several finds from different eras, and relevelling besides the ones from more recent era, one from medieval era and one limestone capital from the late imperial era.
Outside the church, in proximity to the entrance on the left, numerous remains of human skeletons have been found. These were laid, perhaps following the rearrangement of other burials, inside tombs with coffered stone ceiling together with thirteen skulls arranged neatly along the internal perimeter. The only funeral garment is represented by a necklace of twenty wander made with vitreous paste.
In a rectangular room, a semicircular basin divided in two parts and with steps has also been brought to light. It probably served for artisanal activities since in its bottom there are two drainage cups. Inside the basin were found some marble fragments with funerary inscriptions in Latin, probably from Christian burials of the late ancient period (V-VI century AC).
A well was also discovered not far from the church. It is still being studied for its similarities with the well of Cuccuru Naraxi at Settimo San Pietro, and for its discovery near stone artefacts and pottery dating back to XII-X century that could be attributed to the Nuragic age.