நீலகண்ட நகரம் என்பது சங்ககாலச் சேரர் துறைமுகமாகும்.
இந்நகர் பெரிப்ளசு காலத்தில் நெல்சின்டா எனவும் ப்ளைனி காலத்தில் நியாசின்டி எனவும் டாலமி காலத்தில் இது மேல்கிந்தா எனவும் குறிக்கப்பட்டுளது. இது பாண்டியர் ஆளுகைக்குள் இருந்ததாகவும் இங்கிருந்தே மிளகு செங்கடல் துறைமுகங்களுக்கு ஏற்றுமதை செய்யப்பட்டதாகவும் தெரிகிறது.
Then come Naura (Kannur) and Tyndis, the first markets of Damirica or Limyrike, and then Muziris and Nelcynda, which are now of leading importance. Tyndis is of the Kingdom of Cerobothra; it is a village in plain sight by the sea. Muziris, of the same kingdom, abounds in ships sent there with cargoes from Arabia, and by the Greeks; it is located on a river (River Periyar), distant from Tyndis by river and sea five hundred stadia, and up the river from the shore twenty stadia. Nelcynda is distant from Muziris by river and sea about five hundred stadia, and is of another Kingdom, the Pandian. This place also is situated on a river, about one hundred and twenty stadia from the sea...."—The Periplus of the Erythraean Sea, 53-54
- John Watson McCrindle The commerce and navigation of the Erythraean sea. Thacker, Spink & co., 1879, p. 134.
To those who are bound for இந்தியா, Ocelis (On the Red Sea) is the best place for embarkation. If the wind, called Hippalus (Southwest Monsoon), happens to be blowing it is possible to arrive in forty days at the nearest market in India, "Muziris" by name. This, however, is not a very desirable place for disembarkation, on account of the pirates which frequent its vicinity, where they occupy a place called Nitrias; nor, in fact, is it very rich in articles of merchandise. Besides, the road stead for shipping is a considerable distance from the shore, and the cargoes have to be conveyed in boats, either for loading or discharging. At the moment that I am writing these pages, the name of the king of this place is Caelobothras (Keralaputras). Another port, and a much more convenient one, is that which lies in the territory of the people called Neacyndi, Barace by name. Here king Pandion (Pandya) used to reign, dwelling at a considerable distance from the market in the interior, at a city known as Modiera (Madurai). The district from which pepper is carried down to Barace in boats hollowed out of a single tree is known as Cottonara (Kuttanadu).
- Study points to ancient trade connection in Central Travancore
- Gazetteer of the Bombay Presidency: Kola'ba and Janjira. Govt. Central Press, 1883, p. 140.
That Nelkynda cannot have been far from this is clear from the vicinity of the Red Hill of the Periplus. There can be little doubt that this is the bar of red laterite which, a short distance south of Quilon, cuts short the backwater navigation, and is thence called the Warkalle Barrier. It forms abrupt cliffs on the sea, without beach, and these cliffs are still known to seamen as the Red Cliffs. This is the only thing like a sea cliff from Mount D'Elv to Cape Comorin""—Notes on the Oldest Records of the Sea-route to China from Western ASia