The Maharashtra Cabinet has approved the Mumbai Metro Line 11 project, extending Line 4 along the Wadala–Thane–Kasarvadavli route to the Gateway of India. The 17.5 km corridor, comprising 13 km underground and 4.3 km elevated sections, is estimated to cost Rs 23,488 crore and will feature 14 stations. The Mumbai Metropolitan Region Development Authority (MMRDA) will implement the project, with central government support provided through equity and interest-free subordinate debt, while the state government will manage the loan component.

The original alignment from Wadala to CSMT, which traversed congested areas such as Abdul Rehman Street, was revised due to engineering challenges posed by old residential and commercial structures. The new route will pass through Regal Circle, connecting landmarks including the Gateway of India, Flora Fountain, Crawford Market, and Fort. The corridor will intersect the Harbour Line at Reay Road and the Central Line at Sandhurst Road, ensuring improved access for commuters and tourists, with potential stations near Marine Drive and Dhobi Talao.

Metro Line 11 will link with Metro Line 4 at Wadala and Metro Line 3 (Colaba–Bandra–SEEPZ) at CSMT. It will also pass through Sion, offering access to Dharavi, where a major multimodal hub is planned. The interchange will integrate suburban rail, buses, and metro lines, easing congestion on overburdened train corridors. The line will also provide metro access to Nagpada, Bhendi Bazaar, Ballard Estate, and Crawford Market, while bringing the Gateway of India within one kilometre of a station for the first time.

The project will receive approximately Rs 1,338 crore in central equity and Rs 917 crore as interest-free debt, with further support expected from the Japan International Cooperation Agency (JICA). The Mumbai Metro Rail Corporation Limited (MMRCL) will execute the project, with the detailed project report prepared by Delhi Metro Rail Corporation.

Metro Line 11 will operate six-car trains at speeds of up to 80 km per hour, with peak-hour frequency of one train every 2.5 minutes. Daily ridership is projected at 580,000 by 2031, potentially exceeding one million by 2055.