Bay of Bengal

The Bay of Bengal is the northeastern section of the Indian Ocean, sitting between the Indian subcontinent and the Indochinese peninsula, just south of the Bengal region. It covers about 2,600,000 square kilometers (1,000,000 square miles) and is bordered by several South Asian and Southeast Asian countries. To the west and northwest, mainland India forms its boundary; Bangladesh lies to the north; Myanmar is to the northeast; and the Andaman and Nicobar Islands (part of India) define its eastern edge. Its southern limit runs from Sangaman Kanda in Sri Lanka to the northwestern tip of Sumatra in Indonesia.

Major rivers from the Indian subcontinent empty into the bay, including the Ganges, Brahmaputra, Irrawaddy, Godavari, Krishna, Brahmani, Baitarani, Rushikulya, Mahanadi, and Kaveri. Its coastline features many beaches, among them some of the world’s longest natural stretches, such as Cox’s Bazar and Marina. The area also contains diverse ecosystems, notably the Sundarbans, the largest mangrove forest on Earth.

The International Hydrographic Organization sets the bay’s eastern boundary as a line from Cape Negrais in Burma through the larger Andaman Islands, so that all narrow waters between the islands lie east of the line and outside the bay, ending at a point in Little Andaman Island. From there, the boundary follows the southwest limit of the Burma Sea to Sumatra. The southern boundary runs from Adam’s Bridge (between India and Ceylon) and from the southern tip of Dondra Head in Ceylon to the north point of Poeloe Bras.

The bay takes its name from the historical Bengal region, which includes modern-day Bangladesh and the Indian states of West Bengal, Tripura, and the Barak Valley of southern Assam. In ancient Indian scriptures, it may have been called Mahodadhi. The Romans knew it as Sinus Gangeticus, and the Greeks called it the Gulf of the Ganges; old European maps continued using that name.

Historically, the bay had several names tied to powerful maritime kingdoms. In the region of modern Odisha and parts of Andhra Pradesh, it was widely called Kalinga Sagar, after the ancient kingdom of Kalinga. In classical India, it was known as Vaṅgasāgara, and in ancient Tamil literature, it was Vanga Kadal. During the Chola dynasty, under Rajaraja Chola I and Rajendra Chola I around 1014 AD, the bay was referred to as the Chola Sea or Chola Lake. The Northern Circars occupied its western coast, now part of Odisha and Andhra Pradesh. The Kakatiya dynasty also reached this western coastline between the Godavari and Krishna rivers. The Kushanas invaded northern India around the mid-1st century AD, possibly extending to the bay, and Chandragupta Maurya expanded his dynasty across northern India to its shores. In the 16th century, the Portuguese built trading posts at Chittagong and Satgaon. Early Muslim influence in the region came via textile trade routes—one targeting the eastern Arabian Sea, which brought Arab and Persian migrants, and another to the west, leading Buddhist Bengalis to culturally mix with Islam.

Notable historic sites along the bay include: Antarvedi, a popular place of worship in Andhra Pradesh where a distributary of the Godavari River meets the sea; Arikamedu, an archaeological site near Puducherry; the Cellular Jail, a British penal colony built in 1896 on Ross Island in the Andaman Islands; Buddhist heritage sites at Pavurallakonda, Thotlakonda, and Bavikonda near Visakhapatnam; Konark, home to the Sun Temple, a World Heritage Site built in the mid-1200s; the Jagannath Temple at Puri, one of four sacred Hindu pilgrimage sites; Ramanathaswamy Temple at Dhanushkodi, where the bay meets the Gulf of Mannar; the Seven Pagodas of Mahabalipuram, including the Shore Temple, a World Heritage Site from the 8th century; a submerged temple off the Visakhapatnam coast, possibly opposite the Coastal Battery; and Vivekanandar Illam, built in 1842 by the American "Ice King" Frederic Tudor for ice storage and sales.