On Thursday, the Kolkata metro authorities a 'joy-ride' for the media to showcase the country's first underwater section of the metro. The exercise was undertaken after Kolkata Metro scripted history on April 12 when its rake ran through the tunnel under the Hooghly for the first time in the country from the eastern metropolis to Howrah on the other side of the river. After this stretch becomes operational, Howrah Maidan will be the deepest Metro station - 33 metres below the surface - of the country. (Video credit: PTI)