Notes: India’s first underwater metro tunnel will come up in Kolkata, West Bengal, which will pass through the Hooghly River. The tunnel has been constructed 30 metres below riverbed, just a few metres away from the famous Howrah Bridge. It will be connecting two main terminals: Howrah and Sealdah — each of which has a footfall of about 10-12 lakh passengers per day. With the cost of Rs 60 crore, the project is expected to be completed by December 2019. Notably, this is the first time in India that a tunnel has been made under a flowing river.