M4 Update: Technical Test Closures

Some tests are conducting on the entire infrastructure in preparation for the full opening of the line. During test days, which must be performed without passengers, the M4 is closed, and trains are replaced by buses. Night services continue with the NM4 buses as usual.

M4 Closure Dates and Bus BM4 Replacement:

  • June 10 and 11

BM4 Bus Schedule:

  • Weekdays: 7:00-9:30 AM (every 3/4 mins), 6:00-7:00 AM & 9:30 AM-7:30 PM (every 6/7 mins), after 7:30 PM (every 15 mins)
  • Saturdays and holidays: 6:00 AM-7:30 PM (every 7 mins), after 7:30 PM (every 15 mins)


From May 24 to May 27, 2024, Milan’s Blue Line M4 metro will be temporarily closed for crucial technical tests in preparation for its full opening later this year. These tests are necessary to ensure the safety and efficiency of the expanded line, which will increase from 8 to 21 stations and from 13 to 47 trains. An additional closure is planned for June 10-11.

Replacement Bus Services

During the closure, replacement bus services (BM4) will operate with the following frequencies:

  • Weekdays:
    • 7:00 – 9:30 AM: Every 3-4 minutes
    • 6:00 – 7:00 AM and 9:30 AM – 7:30 PM: Every 6-7 minutes
    • After 7:30 PM: Every 15 minutes
  • Saturdays and Public Holidays:
    • 6:00 AM – 7:30 PM: Every 7 minutes
    • After 7:30 PM: Every 15 minutes

Key Stops for Replacement Buses

The BM4 buses will stop at several key locations, including:

  • Linate Airport: Opposite arrivals, near Gate 8
  • Viale Forlanini: At the pedestrian overpass
  • Repetti: Viale Forlanini, near Via Cavriana
  • Stazione Forlanini: Viale Corsica 91
  • Argonne: Viale Argonne 42
  • Susa: Viale Argonne, near Piazzale Susa
  • Dateo: Piazzale Dateo
  • Tricolore: Corso Concordia, near Piazza del Tricolore
  • San Babila: Via Visconti di Modrone
  • Largo Augusto: Via Cavallotti, near Corso Europa (towards Duomo)
  • Via Larga: Corner with Via San Clemente
  • Duomo: Via Baracchini 1

Additional Alternatives

Other alternative routes include:

  • Bus 973 between Linate and Repetti
  • Bus 54 between Argonne and Dateo
  • Bus 61 between Dateo and San Babila
  • Tram 27 between Forlanini and Piazza Fontana

Night Services

Night buses (NM4) will continue to operate as usual, ensuring connectivity during the overnight hours.