Bay of Bengal in the context of "Gulf"

A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a gulf, sea, sound, or bight. A cove is a small, circular bay with a narrow entrance. A fjord is an elongated bay formed by glacial action.The term embayment is also used for related features, such as extinct bays or freshwater environments.

A bay can be the estuary of a river, such as the Chesapeake Bay, an estuary of the Susquehanna River. Bays may also be nested within each other; for example, James Bay is an arm of Hudson Bay in northeastern Canada. Some bays are large enough to have varied marine geology, such as the Bay of Bengal (2,600,000 km or 1,000,000 sq mi) and Hudson Bay (1,230,000 km or 470,000 sq mi).

The Ptolemy world map is a map of the world known to Greco-Roman societies in the 2nd century. It is based on the description contained in Ptolemy's book Geography, written c. 150. Based on an inscription in several of the earliest surviving manuscripts, it is traditionally credited to Agathodaemon of Alexandria.

Notable features of Ptolemy's map is the first use of longitudinal and latitudinal lines as well as specifying terrestrial locations by celestial observations. The Geography was translated from Greek into Arabic in the 9th century and played a role in the work of al-Khwārizmī before lapsing into obscurity. The idea of a global coordinate system revolutionized European geographical thought, however, and inspired more mathematical treatment of cartography.

India, officially the Republic of India, is a country in South Asia. It is the seventh-largest country by area; the most populous country since 2023; and, since its independence in 1947, the world's most populous democracy. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is near Sri Lanka and the Maldives; its Andaman and Nicobar Islands share a maritime border with Myanmar, Thailand, and Indonesia.

Modern humans arrived on the Indian subcontinent from Africa no later than 55,000 years ago. Their long occupation, predominantly in isolation as hunter-gatherers, has made the region highly diverse. Settled life emerged on the subcontinent in the western margins of the Indus river basin 9,000 years ago, evolving gradually into the Indus Valley Civilisation of the third millennium BCE. By 1200 BCE, an archaic form of Sanskrit, an Indo-European language, had diffused into India from the northwest. Its hymns recorded the early dawnings of Hinduism in India. India's pre-existing Dravidian languages were supplanted in the northern regions. By 400 BCE, caste had emerged within Hinduism, and Buddhism and Jainism had arisen, proclaiming social orders unlinked to heredity. Early political consolidations gave rise to the loose-knit Maurya and Gupta Empires. Widespread creativity suffused this era, but the status of women declined, and untouchability became an organised belief. In South India, the Middle kingdoms exported Dravidian language scripts and religious cultures to the kingdoms of Southeast Asia.

The Indian subcontinent is a physiographic region of Asia below the Himalayas which projects into the Indian Ocean between the Bay of Bengal to the east and the Arabian Sea to the west. It is now divided between Bangladesh, India, and Pakistan. Although the terms "Indian subcontinent" and "South Asia" are often also used interchangeably to denote a wider region which includes, in addition, Bhutan, the Maldives, Nepal and Sri Lanka, the "Indian subcontinent" is more of a geophysical term, whereas "South Asia" is more geopolitical. "South Asia" frequently also includes Afghanistan, which is not considered part of the subcontinent even in extended usage.

Southeast Asia is the geographical southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of mainland Australia, which is part of Oceania. Southeast Asia is bordered to the north by East Asia, to the west by South Asia and the Bay of Bengal, to the east by Oceania and the Pacific Ocean, and to the south by Australia and the Indian Ocean. Apart from the British Indian Ocean Territory and two out of 26 atolls of the Maldives in South Asia, Maritime Southeast Asia is the only other subregion of Asia that lies partly within the Southern Hemisphere. Mainland Southeast Asia is entirely in the Northern Hemisphere. Timor-Leste and the southern portion of Indonesia are the parts of Southeast Asia that lie south of the equator.

The region lies near the intersection of geological plates, with both heavy seismic and volcanic activities. The Sunda plate is the main plate of the region, featuring almost all Southeast Asian countries except Myanmar, northern Thailand, northern Laos, northern Vietnam, and northern Luzon of the Philippines, while the Sunda plate only includes western Indonesia to as far east as the Indonesian province of Bali. The mountain ranges in Myanmar, Thailand, Peninsular Malaysia, and the Indonesian islands of Sumatra, Java, Bali, Lesser Sunda Islands, and Timor are part of the Alpide belt, while the islands of the Philippines and Indonesia as well as Timor-Leste are part of the Pacific Ring of Fire. Both seismic belts meet in Indonesia, causing the region to have relatively high occurrences of earthquakes and volcanic eruptions, particularly in the Philippines and Indonesia.

The Indian Ocean is the third-largest of the world's five oceanic divisions, covering 70,560,000 km (27,240,000 sq mi) or approximately 20% of the water area of Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by the Southern Ocean or Antarctica, depending on the definition in use. The Indian Ocean has large marginal or regional seas, including the Andaman Sea, the Arabian Sea, the Bay of Bengal, and the Laccadive Sea.

Geologically, the Indian Ocean is the youngest of the oceans (being directly preceded by the Tethys Ocean, which fragmented into the Mediterranean Sea and the Indian Ocean only 20 million years ago), and it has distinct features such as narrow continental shelves. Its average depth is 3,741 m. It is the warmest ocean, with a significant impact on global climate due to its interaction with the atmosphere. Its waters are affected by the Indian Ocean Walker circulation, resulting in unique oceanic currents and upwelling patterns. The Indian Ocean is ecologically diverse, with important ecosystems such as coral reefs, mangroves, and sea grass beds. It hosts a significant portion of the world's tuna catch and is home to endangered marine species. The climate around the Indian Ocean is characterized by monsoons.

The Maurya Empire was a geographically extensive Iron Age historical power in South Asia with its power base in Magadha. Founded by Chandragupta Maurya around c. 320 BCE, it existed in loose-knit fashion until 185 BCE. The primary sources for the written records of the Mauryan times are partial records of the lost history of Megasthenes in Roman texts of several centuries later; and the Edicts of Ashoka. Archaeologically, the period of Mauryan rule in South Asia falls into the era of Northern Black Polished Ware (NBPW).

Through military conquests and diplomatic treaties, Chandragupta Maurya defeated the Nanda dynasty and extended his suzerainty as far westward as Afghanistan below the Hindu Kush and as far south as the northern Deccan; however, beyond the core Magadha area, the prevailing levels of technology and infrastructure limited how deeply his rule could penetrate society. During the rule of Chandragupta's grandson, Ashoka (ca. 268–232 BCE), the empire briefly controlled the major urban hubs and arteries of the subcontinent excepting the deep south. The Mauryan capital (what is today Patna) was located in Magadha; the other core regions were Taxila in the northwest; Ujjain in the Malwa Plateau; Kalinga on the Bay of Bengal coast; and the precious metal-rich lower Deccan Plateau. Outside the core regions, the empire's geographical extent was dependent on the loyalty of military commanders who controlled the armed cities scattered within it.