Three dynasties, namely the Chera, Chola and Pandya, ruled the area of present-day Tamil Nadu and Kerala. The recent excavations in Alagankulam archaeological site suggests that Alagankulam is one of the important trade centre or port city in Sangam Era. Numismatic, archaeological and literary sources corroborate that the Sangam period lasted for about six centuries, from 300 BC to AD 300. The early history of the people and rulers of Tamil Nadu is a topic in Tamil literary sources known as Sangam literature. The date of the celt was estimated at between 1500 BCE and 2000 BCE. Mahadevan claimed that the find was evidence of the use of the Harappan language, and therefore that the "Neolithic people of the Tamil country spoke a Tamil language".
According to epigraphist Iravatham Mahadevan, this was the first datable artefact bearing the Indus script to be found in Tamil Nadu. Indus valley script between 20 BCEĪ Neolithic stone celt (a hand-held axe) with the Indus script on it was discovered at Sembian-Kandiyur near Mayiladuthurai in Tamil Nadu. About 60 per cent of the total epigraphical inscriptions found by the ASI in India are from Tamil Nadu, and most of these are in the Tamil language. Adichanallur has been announced as an archaeological site for further excavation and studies. The ASI archaeologists have proposed that the script used at that site is "very rudimentary" Tamil Brahmi. In Adichanallur, 24 km (15 mi) from Tirunelveli, archaeologists from the Archaeological Survey of India (ASI) unearthed 169 clay urns containing human skulls, skeletons, bones, husks, grains of rice, charred rice and celts of the Neolithic period, 3,800 years ago.
It is bounded by the Eastern Ghats on the north, by the Nilgiri, the Anamalai Hills, and Kerala on the west, by the Bay of Bengal in the east, by the Gulf of Mannar and the Palk Strait on the southeast, and by the Indian Ocean on the south. Tamil Nadu lies in the southernmost part of the Indian Peninsula and is bordered by the union territory of Puducherry and the South Indian states of Kerala, Karnataka, and Andhra Pradesh. Its capital and largest city is Chennai (formerly known as Madras). Tamil Nadu (( TamiḻNāṭu literally 'The Land of Tamils' or 'Tamil Country') is one of the 29 states of India.