Champaran HumSafar Express : इन अजनबी सी राहों में, जो तू मेरा हमसफ़र हो जाये, बीत जाए पल भर में ये वक़्त, और हसीन सफ़र हो जाये. - Piyush Singh

With the completion of UDZ-ADI BG line, another ghat section/hilly train line, fully completed in BG will be added in IR network. Here is the list as remembered by me:-
1. NR:- Kashmir Valley Rail line ; 2. WR:- UDZ-ADI Haldighati Rail line; 3. KR:- Konkan Rail line; 4. CR:- Bhor Ghat line; 5. CR:- Thull Ghat line; 6. CR:- Shindwane Ghats; 7. NFR- SGUJ-NMZ line; 8. NFR:- Halflong Hill line; 9. NFR:- Tripura Ghat line; 10. WR:- Panchpipliya Tunnel; 11. WCR:- Darra Pass line;
12. WCR:- Ratangaon Ghat; 13. ECR:- Gurpa...
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Gujhandi Ghat; 14. ER:- Jamalpur Tunnel; 15. SER:- Sidhwar Ghat.( RNC-BRKA nearing completion); 16. WCR- Budhni Ghat; 17. CR:- DHQ-MJY Ghat; 18. CR:- Adilabad Ghat; 19. SECR:- Bhimalgondi Ghat; 20. SECR:- JBP-NIR Rail line; 21. SECR:- Bhanwar Tonk Tunnel; 22. SECR:- Hazara Tunnel; 23. SER:- Saranda Tunnel; 24. SER:- Padapahar Line; 25. ECoR:- KK Line; 26. ECoR- RK Line; 27. CR:- Yedshi Ghat/Gad Deodari; 28. SWR:- Tinai Ghat/Dudhsagar; 29. SWR:- Shiradi Ghat/BM line; 30. SCR:- Dorabhavi Ghat/Bogada - Chelama; 31. SCR:- Rapuru Tunnel; 32. SWR:- Maa Kali-Durga Ghat; 33. SWR:- Sivadi Ghat; 34. SWR:- Mulanur Ghat; 35. SCR:- Ghat Nandur; 36. SR:- Palghat Gap; 37. SR:- Tenmalai Ghat; 38. NWR:- Debari Tunnel; 39. SER:- Tori-LAD line; 40. ECoR:- Majhigouri Bridge.

Add more, if I missed anything