India’s first underwater metro project is set to completed by March 2022. It is an East-West Project of Kolkata Metro Rail Corporation, which runs partly under the Hooghly river, West Bengal. The new line is expected to carry about 9,00,000 people daily, which comprises of nearly 20% of the city’s population. It will take less than a minute to cross a 520m underwater tunnel, which takes 20 minutes to use the ferry and more than an hour to cross the Howrah bridge.