The Arabian Sea (Arabic: بحر العرب; transliterated: Baḥr al-'Arab; Sanskrit: सिन्धु सागर; transliterated: Sindhu Sagar) is a region of the Indian Ocean bounded on the east by India, on the north by Pakistan and Iran, on the west by Arabian Peninsula, on the south, approximately, by a line between Cape Guardafui, the north-east point of Somalia, Socotra, Kanyakumari (Cape Comorin) in India, and the western coast of Sri Lanka.
The maximum width of the Arabian Sea is approximately , and its maximum depth is , in the Arabian Basin approximately at the same latitude as the southernmost tip of India. The Indus River, the largest river in Pakistan, also known as the Sindhu river, is the largest river flowing directly into this sea; others include the Netravathi, Sharavathi, Narmada, Tapti, Mahi, and the numerous rivers of Kerala in India. The Arabian Sea coast of central India is known as the Konkan Coast, and that of southern India is known as the Malabar Coast.
The Arabian Sea has two important branches — the Gulf of Aden in the southwest, connecting with the Red Sea through the strait of Bab-el-Mandeb; and the Gulf of Oman to the northwest, connecting with the Persian Gulf. Besides these larger ramifications, there are the gulfs of Cambay and Kutch on the Indian coast. Its islands are few, the chief being Socotra, off the African, and the Lakshadweep, off the Indian coast.
Cities on the coast include Karachi and Gwadar in Pakistan, Mumbai (Bombay), Surat, Panjim, Mangalore, and Cochin in India, Aden in Yemen, Salalah in Oman, Chabahar in Iran, Mogadishu in Somalia and Colombo in Sri Lanka.
It is known as the Sindhu Sagar to Indians since the Vedic period of their history, and an important marine trade route in the era of the coastal sailing vessels from possibly as early as the 3rd millennium BCE, certainly the late 2nd millennium BCE through the later days known as the Age of Sail. By the time of Julius Caesar, several well-established combined land-sea trade routes depended upon water transport through the Sea around the rough inland terrain features to its north.
These routes usually began in the Far East or down river from Madhya Pradesh with transshipment via historic Bharuch (Bharakuccha), traversed past the inhospitable coast of today's Iran then split around Hadhramaut into two streams north into the Gulf of Aden and thence into the Levant, or south into Alexandria via Red Sea ports such as Axum. Each major route involved transshipping to pack animal caravan, travel through desert country and risk of bandits and extortionary tolls by local potentiates. These are the reality of the conditions which gave rise to the truth behind the tales of the Arabian Nights stories, and those of Sinbad the Sailor.
So important was this southern coastal route past the rough country in the southern Arabian peninsula (Yemen and Oman today), that the Egyptian Pharaohs built several shallow canals to service the trade, one more or less along the route of today's Suez canal, and another from the Red Sea to the Nile River, both shallow works that were swallowed up by huge sand storms in antiquity. Later the kingdom of Axum arose in Ethiopia to rule a mercantile empire rooted in the trade with Europe via Alexandria.
Ocean trade routes have crossed the Arabian Sea since ancient times, linking the Near East with East Africa, India, Southeast Asia, and China. Historically, sailors in a type of ship called a dhow used the seasonal monsoon winds to cross the water. The sea forms part of the chief shipping route between Europe and India via the Suez Canal, which links the Red Sea with the Mediterranean Sea.