Mumbai Metro Line 7A has achieved a major milestone with the successful completion of its final underground tunnel between Andheri (East) and Chhatrapati Shivaji Maharaj International Airport (CSMIA).

On 14 July, 2025, Tunnel Boring Machine Dhruv (TBM T-60) completed the 1.65 km “upline” tunnel, marking a significant achievement for the Mumbai Metropolitan Region Development Authority (MMRDA). This tunnel is the first underground metro tunnel built by MMRDA and features a 5.6-mtrs. diameter with 1,178 precast concrete rings. The 3.17 km Line 7A corridor comprises 0.94 km of elevated and 2.5 km of underground sections.

Construction began in March 2020, with tunnelling starting in September 2023. TBM Disha completed the down-line tunnel in April 2025, while Dhruv completed the upline now. Over 61 percent of the entire Line 7A corridor is complete. Line 7A will connect Andheri (East) to CSMIA Terminal 2, integrating with Metro Line 3 and future connections to Lines 2A, 6, 8, and 9. The project is expected to be operational by 2026 or 2027, promising faster airport access, improved east-west connectivity, and reduced reliance on congested road routes.