Yet another step towards unearthing the glorious past of the capital of early Cholas

Tamil Nadu plans deep-sea archaeological excavations to uncover ancient maritime trade history along the State's coast.

In an attempt to highlight the maritime trade prowess of the ancient Tamils, the Tamil Nadu State Department of Archaeology has chalked out a plan for a series of deep-sea archaeological excavations along the State’s coast.

While presenting the Tamil Nadu Budget for 2025-26, Minister for Finance Thangam Thennarasu, who also holds the portfolio of Archaeology, announced archaeological excavations, including the first phase of deep-sea excavations between Poompuhar, also known as Kaveripoompattinam — the ancient port city and capital of early Cholas — and Nagapattinam, another important port city nearly 50 kilometres south of Poompuhar.

These deep-sea excavations are expected to unearth treasures and offer valuable insights into the glorious past of Poompuhar, where the Cauvery flows into the Bay of Bengal and which has elaborate mentions in the Sangam literature and Periplus of the Erythraean Sea. (A Periplus is a manuscript that lists the ports and coastal landmarks. In ancient times, it served as a combination of atlas and traveller’s handbook). Both Poompuhar and Nagapattinam served as an important gateway for trade and cultural exchanges, particularly with Southeast Asia. It is believed the ancient city of Poompuhar existed around 2,500 years ago and submerged owing to tidal action.

This is not the first time deep-sea archaeological excavations have been planned off the Poompuhar coast. The TNSDA, in collaboration with a team of the National Institute of Oceanography (NIO) led by renowned archaeologist S.R. Rao, had conducted a series of geophysical surveys of the ocean floor off Poompuhar in the 1980s. Using side-scan sonar, echo sounders, and magnetometers, these surveys revealed the presence of several structures at a depth of 20-30 metres, offering remarkable clues to Poompuhar’s ancient past.

A report published in The Hindu on April 6, 1990, quoting Natana Kasinathan, then Director of the TNSDA, detailed the discovery of a shipwreck 4.5 kilometres offshore, at a depth of 19.5 meters, seaward of Vanagiri near Poompuhar. The vessel, which seems to be made of iron, was found broken into two and was heavily encrusted with marine organisms. While part of the wreck remains visible above the seabed, a major portion lies buried beneath the ocean floor. The report also highlighted another significant discovery — a megalithic structure found at a depth of seven metres, about half-a-kilometre offshore the Fort Museum at Tharangambadi (Tranquebar), which is nearly 20 kilometres south of Poompuhar. Excavations revealed the inner and outer stone circles along with a pebble cairn-like covering, forming a 10-metre-wide megalithic structure.

According to another report published in The Hindu, underwater explorations between 1991 and 1993 uncovered several man-made structures and brick formations beneath the sea. Quoting Mr. Kasinathan, the report said these brick structures could be dated to between the Second Century BCE and the Fourth Century CE. Black and red ware ceramics were also discovered near the submerged structures. The report also noted that in 1997, divers found remnants of a structure built with laterite stones during the exploration.

In 2004, the hydrographic survey ship INS Darshak, deployed by the Eastern Naval Command off the coast of Poompuhar, discovered a U-shaped structure at a depth of 23 metres. The vessel also recovered the remains of a Dutch ship, believed to have been sunk by the British near the end of the 18th Century. Among the recovered artefacts were three lead ingots, each approximately one metre long and weighing around 80 kilograms. The ingots bore the marking ‘W. Blackett’, presumably the name of the British manufacturer. Another marking, ‘1792’, was presumably the year of manufacture. The ingots had a heart-shaped inscription ‘Vior’ — the emblem of the Dutch East India Company. A two-metre-long cannon was also discovered from the ocean floor, The Hindu reported on April 9, 2004.