India's Mumbai has inducted four air-conditioned rakes in its fleet for the first time to commence 10 air-conditioned train services on its Central line from Thursday, said a statement from the Indian Railways Wednesday.

Spread over 390 km, Mumbai Railway operates 2,342 train services carrying 7.5 million commuters daily and is the busiest commuter rail system in the world. It is spread across three corridors, Western, Central and Harbour lines.

The mainline of the Central corridor, where the new air-conditioned services are introduced, spreads from Chhatrapati Shivaji Maharaj Terminus (CSMT) to Kalyan Junction for a distance of 55 km.

Mumbai's western line has already been operating air-conditioned coaches since 2017 and earlier this year had introduced one air-conditioned rake on its trans-harbour route.

The railways had two classes, first class and second class, with the fare for the first-class travel being 7-10 times the second-class fare, while the fare for air-conditioned trains is 1.3 times the first-class fare.