Walls of Padua
The Walls of Padua (Italian: "cinta muraria di Padova") are a complex of defensive works around the Italian city of Padua, designed to defend it from hostile attack. It was built in 4 phases. Phases. Roman. Of the walls built during the ancient Roman era, the only traces to survive are those incorporated into the foundations of certain palazzi. The route of this wall corresponded to a meander of the river Medoacus (now the Brenta River) in which developed Padua's first urban centre. 13th century. The "Mura Duecentesche" ("13th century walls"; also known as the "mura  comunali" or "mura medievali") were built at the start of the 13th century by the Comune of Padua. Their route was delimited by the two branches of the Bacchiglione, the Tronco Maestro and the Naviglio Interno, which came to be used as defensive ditches. There are several remains of them around the Castello and near Porta Molino. More minor remains are to be found in the Riviera Tito Livio and Riviera Albertino Mussato; the only gates to remain from this wall are the main north gate, Porta Molino (or Molini, after several mills in the area which functioned up to  the early 20th century), and the main west gate, Porta Altinate (named after the road to Altino which began here). The Porta Molino's upper stories were used at the end of the 19th century as a reservoir the town's first drinking water system, though tales of the tower being used as an observatory by Galileo Galilei during his time in the city are probably false. The Porta Altinate fronted onto the Naviglio Interno, crossed by an ancient Roman three-arch bridge (the Naviglio and the bridge were buried in the 1960s), and in 1256 this gate was stormed  and destroyed by crusaders fighting against Ezzelino da Romano (as recorded in an inscription recorded by Carlo Leoni). It was rebuilt in 1286. 14th century. The "Mura Carraresi" ("Carraresi's Walls") were built by the Carraresi in the 14th century and followed a route which corresponds almost entirely to that of the later 16th century wall. Almost nothing remains of them, since they were demolished during the War of the League of Cambrai to create the Renaissance wall - some sections can be seen in via delle Dimesse, near the Prato della Valle. 16th century. The "Mura Cinquecentesche" ("16th-century Walls ; also known as the Mura rinascimentali" or "Veneziane") were built during the first decades of the 16th century by the Venetian Republic under the local leadership of the condottiero Bartolomeo d'Alviano. The west flank was protected by the canal still known as the "fossa Bastioni". Most of the walls and nearly all the gates survive unbroken apart from sections demolished in the 1960s to build the new Ospedale Civile. The gates include: Later use of the walls. Recent discussions about the city walls have discussed creating a green ring around them, a green lung as envisioned by the town planner  Luigi Piccinato, though recent works seem to be moving in the opposite direction (including the controversial monument "Memory and Light" by the architect Daniel Libeskind in the golena of the Porte Contarine).