Milan - or Milano, in Italian - is a relatively small town, with
Piazza Duomo (or the Cathedral Square) as its historical and geographical umbilicus.
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The
city centre is enclosed by an inner ring, corresponding to the walls which protected Milan during the Middle Ages. (Those walls, by the way, are no longer there).
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A wider area is enclosed by the ’Viali’ or ‘
Bastioni’, the ring of the 16th-century Spanish Walls (almost completely gone, too). Driving in this area involves a
congestion charge.
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The area outside the Bastioni is more recent. Its outer boundary is the
Circonvallazione Esterna where trolley-buses run, a ring made up of the alleys around the near outskirts.
.:. Further out the real outskirts begin.