Dear LRC It is true that inscriptions of Kings of South were not available much beyond Vindhya . As Vincent Smith observed, the southern part of the country is almost neglected when the Archaeology research was started by the Govt. of India .But if you can accept Silapathikaram, Agananooru, Pathitrupathu , and Purananooru authors' statements, you will have many evidances. Silapathikaram tells about Imayavaramban(already has gone upto Himalayas), his son Senguttuvan has gone north to bring stones from Himalayas and the Kings of South supported him.Northern King Balakumaran with his sons Kanakan and Vijayan with 51 other small kingdoms' forces opposed Senguttuvan. The battle was on the banks of Ganges and Senguttuvan won the battle, and he stayed there for 32 months. With the stones on the back of Kanaka Vijayan he marched back to his country. This statement of Silapathikaram is acknowledged by Paranar and Mamoolanar and Marolakkathu Nappasalayar in Purananooru, Agananooru, Pathitrupathu..
Karikalan's Chola's Pass - it is detailed already. The distance and mountains never stopped Tamil kings. 2. Neelakanta Sastri's 'A History of South India - from Pre Historic Times to the Fall of Vijayanagar' is the book which will clear all the doubts in this subject. This was published by Oxford University Press. 3. Gangai Konda Rajendra Chozhan - In the war expedition to Ganges, Arayan Rajarajan has to face the Kings of Western Chalukyas, Masuni Desam(Nagas), Ottara Nadu(Indra Dattan), Dharmapalan of Dhandapukthi, and Govindachandran of Bengal. He faced them and made it. Samantha Senan, a chieftain in Arayan Rajarajan's troops stayed in Bengal and later started Sena Vamsam of Bengal. 'Panditha Chozhan' is one of the names Rajendra have. Rajendra was inspired more by Silapathikaram and was having the wish to go upto Ganges. - Neelakanda Sastri. /Tiruvalangadu plates. So, these war expeditions of Southern Kings to the north could have been possible. (Pre historic kings have also gone to north and from north to south - there are many examples like, Agastiya having asramas from Himalayas to Kanyakumari, Ravanan went to Ayothi prior to Ramayanam period)
Dear SPS Thanks and appreciate for keeping in mind and informing. But I want to impose some punishment. So, your next visit is sure with lunch in my house. Bring as much as our members as you can. I keep waiting.