The Mumbai Railway Vikas Corporation Ltd (MRVC), in collaboration with Central and Western Railways, has initiated a feasibility study to examine the underground conversion of key suburban rail corridors in South Mumbai. The project aims to modernise ageing surface-level lines, decongest the city, unlock valuable railway land, and improve integration between local trains and other transport networks.Under Western Railway, MRVC has proposed converting the Churchgate–Mumbai Central corridor, a 5 km stretch, into an underground route that would resurface near Mumbai Central. On the Central Railway side, a study is being undertaken for two new suburban lines between Chhatrapati Shivaji Maharaj Terminus (CSMT) and Parel, spanning about 8 km. Options being assessed include underground, elevated, at-grade, or hybrid alignments.The proposed corridors are planned strictly on railway-owned land, minimising private acquisition and displacement. A major interchange hub at Byculla is also under consideration, which could enhance connectivity across Mumbai’s transport systems.Consultants will evaluate multiple objectives, such as freeing up prime land parcels in South Mumbai for redevelopment or public use, improving suburban rail efficiency through faster and more frequent services, and better integration with other modes like the Metro, BEST buses, and long-distance trains. The study will also incorporate global best practices from cities such as London, New York and Tokyo.On the technical front, assessments will include station location options, transition zones, and tunnel designs, comparing twin-bore against multiple single-bore systems in terms of cost, complexity, and safety. A comprehensive cost–benefit and financial feasibility analysis will shape funding and sustainability plans.This initiative signals a bold reimagining of South Mumbai’s suburban rail spine. If implemented, it could transform daily commuting for millions while unlocking high-value land and modernising the city’s transport infrastructure.