What are blue holes?
Blue holes get their name from the intense, contrasting dark blue colour of the water inside them, as these holes are quite deep. This strong blue contrasts with the clear turquoise of the surface waters of the continental shelves surrounding these blue holes.
A blue hole is nothing more than an underwater cave, but instead of being horizontal, imagine it vertical.
The origin of blue holes dates back to the ice ages, when the sea level was at least 100 metres below sea level; exactly, these holes were formed when they were not yet submerged in the sea. After the last ice age, the water level rose and completely covered the blue holes, leaving them submerged.
Blue Hole Dahab
Our particular blue hole, just a few kilometres north of Dahab, is one of the most famous dive sites in the Red Sea. One thing that sets it apart from others is that this hole is attached to a cave system. A passageway suitable for technical diving connects the rock wall of the Blue Hole to the open sea, known as ‘the Arch’. But we talk about this in more detail here.
As blue holes are protected from the currents and waves of the open sea, they often host unique ecosystems. The reef wall of the ‘blue hole’ in Dahab is completely full of life and many colours. When diving in these geological formations, you will probably find it more difficult to observe the contrast in depth, you can expect an experience more similar to diving in caverns, caves or cenotes than in the open sea.
In addition to divers, in recent years it has become a point of attraction for freedivers. Freedivers find ideal conditions for depth training: easy access, no current and very close to the coast.
To dive in the Blue Hole you need an advanced qualification and to have previously dived in Dahab. If you are a freediver, you must be certified, as there are no introductory courses at the Blue Hole.