Namma Metro: Bengaluru's Namma metro 2nd longest after Delhi metro - The Economic Times
Bids invited for construction of underground stretch of corridor-5 of Chennai Metro | Urban Transport News
CMRL issues four underground civil tenders for Chennai Metro Phase 2 | Urban Transport News
Does any Indian city has underground metro rail system? If not, why? - Quora
Is underground transit bad for your health? - USC News
Mumbai first underground Metro 3 line trials Successfully Commence 5 Points
Underground Metro ideal, but not viable - Metro Rail News
Mumbai's First Underground Metro Line To Be Operational Soon In 2023
List of metro systems - Wikipedia
Bangladesh's First Underground Metro Rail To Start Its Construction - The InCAP
Four underground Chennai metro stations ready for trains
Going deeper underground: subway stations that will make you think "wow that's a really cool subway station!" | Intrepid Travel Blog - The Journal
First underground metro train in Chennai to run from Sunday | Chennai News - Times of India
Learning Le Metro: Basic Tips for Paris' Underground Arteries by Rick Steves
Chennai Metro | Underground Metro Station - YouTube
Oldest metros in Europe: London Underground to Moscow Metro
Subway | History, Transportation, Cities, & Facts | Britannica
Kolkata to get first underground metro station in 25 years | Kolkata - Hindustan Times
Chennai Metro's First Underground Stretch To Be Inaugurated Today
First underground metro train in Chennai to run from Sunday - The Hindu BusinessLine
Trial Runs on Bangalore Metro's Underground Section Finally Begin - The Metro Rail Guy
Mumbai Metro Line 3: Everything you need to know | Housing News
