RBI Grade B Officers 2017 jun Paper

(3) India’s first underwatermetro rail tunnel, named EastWest Metro, was in May 2017completed underthe Hooghlyriver for establishing metrolink between Howrah andKolkata. Rachna, a giant tunnel-boring machine (TBM), wasdeployed to dig the underwatertunnel that runs a lengthof 502 metres under the river.