Aliwal is famous for its raggedtooth sharks, which can be seen in large numbers between August and November
Named after the near-sinking the three-masted vessel "Aliwal" in 1849, Aliwal Shoal is part of a large offshore reef complex off the south coast of KwaZulu/Natal. When divers refer to Aliwal Shoal they usually mean the part of the reef named the Crown, a narrow ridge parallel to the coastline is about 5 kilometres (3.1 miles) offshore. It is inside the sanctuary zone of the 126 km2 Marine Protected Area that was established in 1991. The shallowest part, extending to within 6 meters (20 feet) of the surface, is at the north end of the Crown. To the north the bottom slopes down relatively steeply, and to the sides the slope is less. The shoal is about 380 meters (1,250 feet) wide to the north, narrower to the south, and then spreads out towards the coast in the section known as the Ridge. Average depth of the Crown is about 12.5 meters (41 feet), and the Ridge is about 19.5 meters (64 feet) average depth, with a few isolated pinnacles.
All diving is from RIBs and although the ride usually takes around 25 minutes, it often provides an enormous amount of excitement due to breakneck speeding through big waves and huge swell.
Divers may encounter many ragged tooth, tiger and whale sharks, manta rays, and dolphins. The Shoal is known especially for its abundance of Grey nurse sharks (known locally as ragged tooth sharks or "raggies") between July and November when the sharks congregate there to mate. Large numbers of scorpion fish, lionfish hawk fish, and numerous species of butterfly fish and angel fish can be seen on nearly every dive. Huge resident potato bass are seen often enough to earn individual nicknames with divers.
Popular diving sites on the Aliwal Shoal include The Cathedral (an amazing hole in the reef), The Pinnacles, The North Sands and, of course, Raggie Cave and Shark Alley.
Despite the name of the reef complex, there is no Aliwal wreck here, but divers can enjoy the wreck of the SS Nebo, which sank on this spot in 1884 while carrying bridge supports up the coast. The second interesting wreck in the area is the Norwegian bulk carrier Produce that hit the shoal on 11th May 1974. Both wrecks lie at around 30 meters (90feet) of water and provide an excellent habitat for many species of fish, invertebrates, eels, corals, and sponges.