The Mumbai Metropolitan Region Development Authority (MMRDA) is advancing the creation of a 70- km underground tunnel network in the city, costing Rs 1.05 lakh crore.

The project, designed as a 'third mode of urban mobility,' aims to alleviate traffic congestion by complementing the city's existing rail and road systems. The first phase will link Worli to Chhatrapati Shivaji Maharaj International Airport (CSMIA) over a 16 km stretch. The longest tunnel, connecting south Mumbai to Borivali, will span 44 km. The project will offer high-capacity underground corridors, easing traffic on arterial routes like the Western Express Highway and SV Road.

Expected to redefine Mumbai’s mobility, it promises smoother, faster, and safer commutes. Feasibility studies are underway to ensure the technical, economic, and environmental viability of the plan, which will be executed in phases to match future demand.