Red Sea, or the Erythraean Sea, is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. The sea is underlain by the Red Sea Rift which is part of the Great Rift Valley.
Origin of name
The name of the sea may signify the seasonal blooms of the red-coloured Trichodesmium erythraeum near the water's surface. 
In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez (leading to the Suez Canal).
The earliest known exploration of the Red Sea was conducted by ancient Egyptians, as they attempted to establish commercial routes to Punt. One such expedition took place around 2500 BC, and another around 1500 BC (by Hatshepsut). Both involved long voyages down the Red Sea. The Biblical Book of Exodus tells the story of the Israelites' crossing of a body of water, which the Hebrew text calls Yam Suph. Yam Suph was traditionally identified as the Red Sea. The account is part of the Israelites' escape from slavery in Egypt. Yam Suph can also been translated as Sea of Reeds.
In the 6th century BC, Darius the Great of Persia sent reconnaissance missions to the Red Sea, improving and extending navigation by locating many hazardous rocks and currents. A canal was built between the Nile and the northern end of the Red Sea at Suez.
In the late 4th century BC, Alexander the Great sent Greek naval expeditions down the Red Sea to the Indian Ocean. Greek navigators continued to explore and compile data on the Red Sea. Agatharchides collected information about the sea in the 2nd century BC.
The Periplus of the Erythraean Sea ("Periplus of the Red Sea"), a Greek periplus written by an unknown author around the 1st century AD, contain a detailed description of the Red Sea's ports and sea routes. The Periplus also describes how Hippalus first discovered the direct route from the Red Sea to India.
The Red Sea was favored for Roman trade with India starting with the reign of Augustus, when the Roman Empire gained control over the Mediterranean, Egypt, and the northern Red Sea. The route had been used by previous states but grew in the volume of traffic under the Romans. From Indian ports goods from China were introduced to the Roman world. Contact between Rome and China depended on the Red Sea, but the route was broken by the Aksumite Empire around the 3rd century A D.
During the Middle Ages, the Red Sea was an important part of the Spice trade route. In 1513, trying to secure that channel to Portugal, Afonso de Albuquerque laid siege to Aden. but was forced to retreat. They cruised the Red Sea inside the Bab al-Mandab, as the first European fleet to have sailed these waters.
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