Crossroad toward the Arno Valley, has represented also for a
long time an important place for the commercial exchanges also
in very ancient ages. The parishes and particularly those of
San Giusto in Salcio, San Polo in Rosso and Spaltenna represented the fulcrum around which the first nucleuses were formed. All the territory is studded from numerous castles which had to the strong influence of noble families, and subsequently, to the necessity of the Florentine Republic to equip of defensive outposts. Montegrossi, Vertine, San Sano, Lecchi, Cacchiano, Tornano, Castagnoli, Lucignano and Meleto are some of the many castles of the age that, in the most greater part, were turned into villas. A particular case is constituted by the castle of Brolio, center of the Ricasoli family: its fortifications go up to the end of the XV century and they represented one of the first examples of posting of defense provided of bastions. The complex was restructured then in the XIX century from the Baron Bettino Ricasoli, that turned it into a villa in new-Gothic style.
The presence of so many castles it determined the development of it as important center of exchanges. The city develops him around its characteristic plaza of lengthened triangle form, on which leaned out the shops.