Who says South India does not have Gatimaan. It is called Vaigai Express. - Thamizh Maran

Metro train means Rapid transit or mass rapid transit (MRT), also known as heavy rail, metro, subway, tube, U-Bahn or underground, is a type of high-capacity public transport generally found in urban areas.
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A premetro design means that an underground rapid transit system is built in the city center, but only a light rail or tram system in the suburbs....
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Conversely, other cities have opted to build a full metro in the suburbs, but run trams in city streets to save the cost of expensive tunnels.
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There are 10cities with metro rail connectivity in INDIA:
Kolkata(WB)
Chennai(TN)
Delhi.
Bangalore(Karnataka)
Gurgaon(Haryana)
Mumbai(Maharashtra)
Jaipur(Rajasthan)
Kochi(Kerala)
Lucknow
Ahmedabad
Hyderabad
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From This above metro trains which one is best and most use to relieve people from traffic