structural:expansion, information:classification
Trade routes

The Arabian Sea has been an important marine trade route since 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, India with transshipment via historic Bharuch (Bharakuccha), traversed past the inhospitable coast of modern-day Iran, then split around Hadhramaut, Yemen 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 transhipping to pack animal caravan, travel through desert country and risk of bandits and extortionate tolls by local potentates.

This southern coastal route past the rough country in the southern Arabian Peninsula was significant, and 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.