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RMM SBC via CDM KPD suggested because the train will connect many pilgrimage centres -- Thiruvannamalai, Cuddalore, Chidambaram, Sirkazhi, Mayiladuthurai, Thiruvarur, Ramanathapuram, Rameshwaram. Can act as a train to Nagapattinam, Velankanni, Nagore, Karaikal, Thirunallar, as these towns are nearer MV/ TVR. Also, Katpadi gets connection with these towns which is missing now.
Distance may be more by around 180 kms, but it is justified.

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SBC can have daily one train but on 3 different routes on different days. Biweekly via MV CDM VM KPD, Biweekly via TJ KRR SA HSRA, tri weekly via MDU KRR SA KJM.

Also KIK SBC ONT is very much necessary. 3 days via TJ TPJ SA, 2 days via MV CUPJ SA, 2 days via MV VM KPD.