Kolkata Metro: The only Metro of IR. কলকাতা মেট্রো : তিলোত্তমার জীবন রেখা ।। - PPG

I wish to travel from Chennai to Thiruvannamalai. Since my time of travel is not very fixed, I'd like to take the most frequently available train / route
I'd prefer to do the entire trip by train, preferably in reserved compartments.,
However since direct trains are very few, I'm ready to change trains and / or take the last leg by bus. What are the ideal and most frequent alternatives ?
(a)...
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direct trains - I see these as very few
(b) probably I should change at Villupuram - if so what is / are the best alternative(s) ? should I take the Villupuram - Thiruvannamalai by bus ? how far is the Villupuram bus stand from villupuram train station ? how much do autos charge ? could I request tips and guidance please ..
(c) probably I should change at Vaniyambadi or some place on the MAS - bnagalore lain - IF so could I request tips and guidance please
(d) what other alternatives
thanks in advance *
best regards
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