12669/12670 Ganga Kaveri Expresses were introduced as 139/140 GK Exp in 1977 just before Coromandel bearing numbers 141/142 was introduced. This train was the dream child of one of the Rly Ministers late Kamalapathi Tripathi, who hailed from Varanasi and wished to connect the pilgrim towns of Benares and Rameshwaram. At that point of time they were a pair of BG/MG trains. The MG train would come from Ramwshwaram to Chennai Beach and on adjacent BG platform the pairing BG train from Beach to Varanasi would be standing. After the passengers disembarked and boarded the BG train it would leave for Varanasi via Gudur Vijayawada Balharshah Nagpur Itarsi Jabalpur & Allahabad.
The BG trains, if I remember right, used to leave both...
more... ends twice a week, at 7/8 am and reach destination at about 5 pm.
Later following the disastrous accident to Tamilnadu Express, all SF trains were slowed down and these trains reached the destination only at 9/10 pm. Also as the interchange system at Madras Beach from BG to MG was not very popular, it was discontinued and only the BG service was retained and shifted to Central. Later during the time of Lalu Prasad Yadav as RM, this train got extended to Chhapra.