The area today known as Porta Palazzo takes his name from the gate marking the entry, through the boundary walls, to the old fortified Roman town Augusta Taurinorum. The Porta Principalis Sinistra, indeed, was also named "Palatina" because it was close to the Palace seat of the ancient Senate. The area took long time, actually, to develop as it was "extra moenia", out of boundaries. We have to wait until Vittorio Amedeo II, at the beginning of 1700, who, weighing the importance raised by the area named "Contrada di Porta Palazzo" as a transit spot to get into and get out of the town, and following the purpose to set off this gate with a square properly welcoming visitors, entrusted Sicilian Architect Filippo Juvarra, with a design to enlarge the district. In this way born embryonal piazza della Repubblica (at the time piazza Vittoria). With the building of the square, the link between the town and Borgo Dora occurred. The present "Balôn", was originally a rural area inhabited, at Roman time, by farmers. During the Middle Age, the area became a City administrative district, peopled by farmsteads, watermills, vegetable gardens, at first, and by some early stage industrial nucleus, around 1500.
Several canals, drawn by the Dora river, became a precious source of energy for little factories and for a powder keg. At the beginning of XXIX Borgo Dora appeared, thus, as a lively and prosperous part of the town. With Napoleone's arrival, in 1800, who orders to dismantle Turin defensive walls, (and also those belonging to other Piedmont towns), Porta Palazzo became, in every respect, a part of the town. With different designs and overlapping phases, piazza della Repubblica was completed in 1837, and took the name of piazza Emanuele Filiberto. With his 51.300 mq it's the largest in Turin. The enhancement of corso Giulio Cesare followed and, to give a way out to this steering road, the bridge over the Dora, named ponte Mosca from his engineer, was built. Since then no more great town planning changes occurred: several intervention on private buildings, Mauriziano Hospital disembowelment to make room for Galleria Umberto I, II World War bombings, final appellation of piazza della Repubblica in 1946, have marked the development of the area of the district till today. The enlargement of the market in the Square up to become the largest open air market in Europe, the loss for Borgo Dora of his pre-industrial leadership (with the electric energy factories displacement) to become the artisans, the antique dealers and the Saturday flea market (called Balon from the ancient presence of a spheristerion) district, have strongly connoted the area. The commercial and popular reality has attracted, during last century, industrial Turin's migratory waves. From South Italy in the sixties, and from the rest of the world, in last decades, up to reach, in 2000 figures, a foreigners percentage in the district of 20%. One hundred thousand visitors at Saturday markets, more than ten thousand inhabitants, hundred of peddlers and fixed shops, the highest concentration of foreign people in the town, all these elements make Porta Palazzo, seat of a part of Turin's historical and architectural heritage, a lively and charming district, root of precious resources but also of complex problems, an urban laboratory which reflects the development of the town in the direction of an European metropolis.