This estimate from a study of the International Association of Public Transport (UITP) and management consultancy Roland Berger was presented in a feature by Railways of the World magazine dedicated to the study itself and current market trends.
UITP and Roland Berger report that in 2023, there were 1,686 km of GoA4 lines, which are lines with unattended operation. 56% of these lines are classified by the association as heavy metro applications, while GoA4 metro represents only 9% of the total length of all metro routes worldwide.
Experts state that approximately 50 GoA4 metro projects, totalling 1,751 km, are currently being implemented. Based on these figures, they conclude that by 2030, the combined length of the GoA4 metro lines will exceed 3,400 km. The Asia-Pacific Region and Europe are identified as the key growth zones for metro systems.
