I have been meaning to write something about the Roman origins of Florence for ages now. We all know Florence as a Firenze, the Medieval city, birthplace of Dante and the cradle of the Renaissance. But whenever I have an aperitivo in Piazza Repubblica, I recollect that it was the centre of the Roman Castrum called Florentia. It was founded in 59BC for the settler-soldiers of Julius Caesar in the form of a military camp.
Piazza Repubblica was and still is, the intersection of the two main Roman roads, the north/south Decumanus and the east/west Cardo. Travellers arrived from Rome on the via Cassia and entered the city from the Porta Romana. The names of the gates of an Italian city almost always tell you where the road leads to. Porta al Prato for example leads to Prato.
A few years ago archeologists excavated the Roman amphitheatre beneath Palazzo Vecchio. Today you can visit the ruins on a guided tour. From the outside you can see the way the road slopes down at the side of Palazzo Vecchio, following the incline of the theatre. Piazzza san firenze had a Temple of Isis. The Roman walls surrounded the city on the northern bank of the Arno, which, believe it or not, was a navigable and important means of supplying the settlement.
the Museo storico topografico, Firenze Com'era, is in via dell'Oriuolo, 24 and has a wonderful dioramo of the ancient city.
Fiesole is much older and was an Etruscan settlement long before the Romans colonised it but it too has marvelous Roman ruins.