20807/8 Hirakund (3 times a week) between Vizag and Amritsar connects the stations south of Bhubaneswar, such as Berhampur, Chhatrpur and Balugaon to/from Delhi
12807/8 Samata Express (5 times a week) connects Rayagada, Muniguda, Ambadola, Kesinga, Titlagarh, Kantamanji, Harishnkar Road, and Khariar Road to/from Delhi
18309/10 Sambalpur - JAT express (4 times a week) provides additional connectivity to/from Delhi for Sambalpur, Jharsuguda, and Rourkela.
The proposed 36th one will be via Kendujhargarh.
In the future there should be trains via Baripada and via the Khurda-Balangir line, when those lines are completed.
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The southern capitals (except Vijaywada) and major cities have less or similar frequency to Delhi.