Bosa has ancient origins, even prehistoric, as demonstrated by the domus de janas, the funerary caves dug into the rock. The Aragonese, who conquered Bosa in 1317, believed that its foundation had even legendary origins (such as arab colony). Situated in an alluvial plain in the historic region of Planargia, Bosa develops along the estuary of the river Temo and due to this favorable position the richness and the popularity that reached already in the Phoenician-Punic and subsequently in the Roman one. From here, the different interpretations etymological of its name: on the one hand bosa would indicate a container in the form of a bowl (comparable to the morphology of the territory on which rises); on the other 'Osa, in Sardinian ancient, which would mean 'estuary'. The historical nucleus, as well as you can visit today, dates back to a period that goes from X to XII century a.c., within which was finished the construction of the romanic church of San Pietro and the Castle of Serravalle, built by the Earls of Malaspina, that from the top of the homonymous hill dominates the town. Inside the castle walls, overlooking the place of arms, is located the church of Our Lady sos Regnos Altos, a palatine chapel that is striking for its essential lines. The medieval structure of Bosa still maintains intact the picturesque charm of the epoch, with singular paths that follow the altimetric curves of the hill, with the stairs that interrupt asymmetrically horizontal path and with its urban structures, archaic and surprising. More suggestions arise from the tanneries (Sas Conzas) that are located along the left bank of the Temo, near the Old Bridge that connects the two banks of the river. This huge industrial complex occupies 4000 square meters and extends through modular structures adjacent to each other. The restoration and enhancement of Sas Conzas has allowed to reach us this rare testimony of industrial archeology, proof of how in the nineteenth century Bosa became the largest tanning center of Sardinia.