The Red Sea, also known as the Erythraean Sea is a seawater inlet of the Indian Ocean that lies between Africa and Asia. The Red is connected to the ocean in the south via the Bab el Mandeb strait and the Gulf of Aden and to its north lies the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez. Saudi Arabia and Yemen border the Red Sea on its Eastern shore and Egypt, Sudan, Eritrea, and Djibouti are found on its Western shore.

The Red Sea is the world's northernmost tropical sea and has a surface area of approximately 438,000 square kilometres and is around 2,250 kilometres long and is 355 kilometres at its widest point, 355 km (220.6 mi) wide. The average depth of the Red Sea is 490 metres and its maximum depth is 3040 metres in the central Suakin Trough. The Red Sea also contains extensive shallow shelves that are famous for their marine life and 2,000 kilometres of coral reefs. The Red sea is a rich and diverse ecosystem that is home to over 1,000 invertebrate species, more than 1200 species of fish, 10% of which are endemic to the region and 200 soft and hard corals. The unique biodiversity of the area was recognised by the Egyptian government when they up the Ras Mohammed National Park in 1983. The area is a very popular draw for diving enthusiasts. Other marine habitats in the Red Sea include: sea grass beds, mangroves, salt pans, and salt marshes.

The Red Sea forms part of the sea roads between Europe, the Persian Gulf and East Asia, and consequently is subject to heavy shipping traffic.