There are 11 states/union territory, metro trains operational in India
1.Delhi
2. Rajasthan:-Jaipur
3. Gujarat:-Ahmedabad
4. Maharashtra:-Mumbai and Navi Mumbai, Pune, Nagpur
5. Karnataka:-Bangalore
6. Kerala:-Kochi
7. Tamilnadu:-Chennai
8. Telangana:-Hyderabad
9. Haryana:-Gurgaon, Faridabad
Part of Delhi NCR metro route.
10, Uttar Pradesh:-Noida, Ghaziabad, Meerut, Agra, Kanpur and Lucknow,
11. West Bengal:-Kolkata
Also a part of Indian Railways, the 17th zonal railway of Indian Railways in 2010.
While Other states have Metro projects, many are still undergoing construction or planned or extending several line in existing metro cities.
Among the mentioned metro route, Delhi Metro has the longest metro network in India around 390 km by covering whole city
Then Bangalore Metro in South India, covers 96 km
Currently Bangalore Metro new lines construction going on Expanding towards North Side and Near IT Hub ORR Ring road, if that project completes then Bangalore Metro is the 2nd longest metro network in South India.