Tidal Waves that destroyed regions of ancient Tamil Nadu

[Anban]

Virarajendra Sir,

Thanks a lot for your informative posts. A Very big land mass going under the sea must have happened very very long ago during the ages of evolution of the human species or before that. These ancient texts gives a different idea that it could have happened some centuries around the first Tamil Sangam era. So when did the first Tamil sangam era happen?