Walls of Milan

The city Milan, Italy, has had three different systems of defending walls. The oldest, Roman walls were developed in two stages, the first in the Republican and the second in the Imperial era. The second wall system was realized in the Middle Ages (12th Century), after the destruction of the city by Frederick I Barbarossa. Finally, the latest wall system was built by the Spanish rulers (16th Century). While very little remains of these walls, their structure is clearly reflected in the urbanistic layout of the city. In particular, modern Milan has two roughly circular rings of streets, namely the "Cerchia dei Navigli" and the "Cerchia dei Bastioni", which essentially correspond to the Medieval and Spanish walls, respectively.

The oldest wall system was built when Milan (the Mediolanum) became a Roman municipium, in 49 BC. It was essentially square, each side about 700 m long. The walls had 6 main gates, which are usually referred to as "Porta Romana" (in Piazza Missori), "Porta Ticinese" (at Carrobbio), "Porta Vercellina" (where Santa Maria alla Porta church stands, "Porta Orientale" (or Porta Argentea, in via San Paolo), "Porta Jovia" (in via San Giovanni sul Muro), and "Porta Cumana" (at the end of Via Broletto, between Via Cusani and Via del Lauro). Note that some of these names (for example, "Porta Romana" and "Porta Ticinese" are also used to refer to gates of later wall systems located in the same area.

In the Imperial era, while Mediolanum was capital of the Western Roman Empire, Emperor Maximian enlarged the city walls; to the east, this was intended to include the Hercules' thermae (located in the surroundings of what are now Piazza San Babila, Corso Europa and Piazza Fontana); to the west, the new walls enclosed the arena. Overall, the new wall systems exceeded 100 hectares. Two gates where added, later referred to as "Porta Nuova" (in what is now the corner between via Manzoni and via Montenapoleone) and "Porta Tonsa" (in the area now known as "Verziere").

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Wikipedia