Indian PM Narendra Modi on Wednesday will inaugurate the first underwater metro service in Kolkata, adding a new dimension to the city's transportation landscape.

The metro tunnel runs beneath the Hooghly River, making it the first underwater metro service in the country.

India's first metro rail connection was also operated in Kolkata.

Spanning a length of 16.6 kilometers, the new route would connect Howrah and Salt Lake, promising to reduce the time needed to travel between the two points and lower the burden on road traffic movement.

Howrah Metro Station is also the deepest metro station in India.

The official X page of Kolkata Metro posted: "Today we are going to create history again. It is a proud moment for us."

Under the river, the metro will traverse a 520-metre stretch in approximately 45 seconds.

The Indian Prime Minister will also inaugurate Kolkata Metro's Howrah Maidan- Esplanade Metro section, Kavi Subhash - Hemanta Mukhopadhyay Metro section, Taratala - Majerhat Metro section (part of Joka- Esplanade line); Pune Metro from Ruby Hall Clinic to Ramwadi stretch; Kochi Metro Rail Phase I Extension project (Phase IB) from SN Junction Metro station to Tripunithura Metro station; Agra Metro's stretch from Taj East Gate to Mankameshwar; and Duhai-Modinagar (North) section of Delhi-Meerut RRTS Corridor.

Prime Minister will also lay the foundation stone for the extension of Pune Metro Rail project phase 1 between Pimpri Chinchwad Metro-Nigdi.