The oldest unchanged service in IR ( sharing the title with 12609/10 MAS-SBC intercity)! MAS-MAQ One mail (12601/02 ) is the grand-daddy of all trains, RPM-Beypore overnight express, started around 1860! But it was extended, train name changed etc many times, so it is missed out usually.
Mail was originally a JTJ-BNC link express connecting to the MAS-Beypore express at JTJ. ( It was still a Chennai-Bangalore train, but the passengers had to transfer to a separate rake at JTJ as locos at that time could not haul very long rakes to accommodate slip coaches). In a short time though, it became an actual slip service connecting to the Beypore mail at JTJ. It used to take almost...
more... 6 hours for the JTJ-BNC stretch! And it had halts at Kuppam, Kolar road ( probably Bangarpet), Malur and Kadugodi ( now Whitefield) and skipped K.R.Puram.