For people getting down at CBE Main.
S26, S15, 1A and 46 go directly to maruthamalai but their frequency is poor.
Bus no 1C can be used to get down at vadavalli and proceed onwards towards maruthamalai. 1C has excellent frequency throughout the day. Onwards one can catch 70 from vadavalli to maruthamalai which also has excellent frequency.
For going upto navavoor pirivu/kalveerampalayam and...
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thomdamuthur, one can catch 64 series from railway station but on opposite side as bus comes from gandhipuram and goes via townhall.
For people getting down at odd hours at CBE Main, they can proceed to Gandhipuram and get direct bus to vadavalli/maruthamalai (70 series). This is useful for people coming by island, YPR-CAN from bangalore.
In return direction, according to a TNSTC conductor, the first bus from maruthamalai to gandhipuram (70 series) is at 3.50 am for every 10 mins. I have personally caught a bus at 4.15am for CBE Main (S26).
Please note, during summers there have been elephant herds spotted around maruthamalai area at odd hours. A herd has also destroyed shops near the maruthamalai bus stand. It would be advisable if people be careful while travelling at odd hours.