This is a long documentary (about 122 minutes) produced by Central Institute of Classical Tamil in India in 2021. It has been posted to YouTube only eight days ago.
Adhichanallur Thamirabarani Civilization--ஆதிச்சநல்லூர் தாமிரபரணி நாகரிகம்-செம்மொழித் தமிழாய்வு
youtube.com
This may be of interest to some members.
Regards,
Palaniappan