The Red Sea has the nearest coral reefs to Europe and the resorts of Sharm el Sheik and Dahab have long been popular with British and German divers. When I first went there Sharm was a six hour drive from Eilat and only frequented by a few hard core divers. There was one hotel and some straw huts for people to stay in and the reefs were pristine. It was great.
However, if you got bent [decompression sickness] you had real problems. There were no hyperbaric [decompression chamber] facilities at all.
After a few years primitive treatment facilities started to appear. This was the decompression chamber at Dahab. It was too bad if you were tall, fat or needed treatment whilst in the chamber.
BTW The most popular dive at Dahab is called The Canyon. It is a deep dive and a dangerous dive. Several people have been killed and more have got the bends. It had an urgent need for hyperbaric facilities.
As Sharm became more popular the hyperbaric facilities were upgraded to this second hand chamber.
Sharm has become a major resort and has its own airport. It attracts a lot of divers and has had to upgrade its medical facilities. It now has a very well equipped hyperbaric treatment centre. There is a large modern chamber [see photos below] , an older backup chamber and full time medical staff. There are also new facilities at Dahab [there is a hill between Sharm and Dahab so moving bent divers the 50 miles from Dahab to Sharm for treatment would not be advisable].
Though the medical facilities have improved the reefs at Sharm and Dahab are not as good as they used to be. The more divers you have visiting a site the more damage it sustains.