The Red Sea is the world’s most northern tropical sea, it formed when Arabia split from Africa due to plate tectonics. It is roughly 1,200 miles (1,900 km) long and, at its widest point, over 190 miles (300 km) wide. It has a maximum depth of 8,200 feet (2,500 m) in the central median trench and an average depth of 1,640 feet (500 m), but there are also extensive shallow shelves.The sea is still widening and it is thought it will become an ocean in time. Water temperatures remain relatively constant at 22-30 °C and temperature and visibility remains good to around 200m (660 feet). The rainfall over the Red Sea and its coasts is extremely low, averaging 0.06 m per year. The Red Sea is one of the most saline water bodies in the world, due to the effects of the water circulation pattern, resulting from evaporation and wind stress.
The Red Sea is a hugely rich and diverse ecosystem. More than 1,100 species of fish, 1000 species of invertebrate ad 200 species of corals have been recorded in the Red Sea, with approximately 10% of these being endemic to the Red Sea. This also includes around 75 species of deep water fish. The special biodiversity of the area is recognized by the Egyptian government, who set up the Ras Mohammed National Park in 1983. Other unique and special marine environments here include salt marshes, sea grass and mangroves.