M4 Metro Line

Client

RTI: IMPREGILO SPA, ASTALDI SPA ANSALDO TRASPORTI SISTEMI FERROVIARI SPA, ATM SPA, ANSALDOBREDA SPA, SIRTI SPA.

Location

Milan

Year

2010-2024

Services

Architectural preliminary and detailed design of the stations, depot and artifacts

Milan’s M4 Line, known as the “Blue Line”, crosses the city from east to west along a route of approximately 15 kilometres, connecting Linate Airport with San Cristoforo railway station. Its 21 stations strengthen the city’s public transport network and improve interchange with the existing metro lines and the suburban railway system.

Fully automated and driverless, the M4 makes it possible to cross Milan in around 30 minutes and to reach Linate Airport from the city centre in just 12 minutes. It is a strategic, innovative and sustainable infrastructure designed to improve mobility, reduce travel times and provide better access to the city’s key urban hubs.

CREW made a significant contribution to the delivery of the project, carrying out the detailed and construction architectural design of 16 stations, 18 ancillary structures and the train depot. Over a period of more than 13 years, a team of over 80 professionals worked on the development of this complex and multifaceted project, addressing the technical, functional and architectural challenges involved in building a new infrastructure within the city’s established urban fabric.

Along the route, the stations are supported by ancillary structures housing emergency exits, ventilation systems and technical equipment. At the western end of the line, the train depot covers an area of approximately 170,000 square metres and is dedicated to the storage and maintenance of the rolling stock.

The design of the underground spaces was guided by the aim of creating functional, intuitive and comfortable environments. The internal layout was developed to ensure clear wayfinding and an efficient organisation of passenger flows, with particular attention to safety, orientation and accessibility for people with disabilities.

The M4 Line is a tangible example of urban transformation: a project that brings together infrastructure, architecture and mobility, regenerating the city’s spaces while respecting Milan’s history and identity and supporting a more connected and sustainable future.