Kolkata/IBNS: Prime Minister Narendra Modi on Wednesday took a ride with some school students inaugurating India's first underwater metro in Kolkata.

The Prime Minister inaugurated three metro routes in Kolkata.

The routes are Esplanade-Howrah Maidan, Majherhat-Taratala and Ruby-New Garia with the first being an underwater one.

Kolkata is also the city where India's first metro service started way back in 1984.

The section of the tunnel that stretches 520 meters under the Hooghly River will be the main point of interest for both KMRC officials and railway enthusiasts across India.

Once the trains have crossed the river, they will then pass through Howrah station, which is the deepest metro station in the country, located 33 meters below the ground.