There are three subway lines in the city which are collectively known as the Milan transportation metro system ATMA. In fact, there are more than 280 km of track and 20 lines. The town is also considered to be the second railway hub of Italy and is made of five important stations. The suburban rail system connects higher Milan to towns like Como or Varese.
The Suburban Railway System (the emblem is an enormous green S on a blue background) operate less often than Metro trains (depending on the line, they vary from 1 to 4 per-hour) but, you’ll find as many as 12 trains/hour in central Milan between important central stations such as Porta Vittoria. These lines are typically marked using a large blue line on maps.