Diving Aliwal Shoal/Cathedral

The dive site Cathedral is an offshore rocky reef with coral on the Aliwal shoal, near Umkomaas in the Kwa-Zulu-Natal province of South Africa.

This is one of the deeper reef sites at Aliwal, and is quite spectacular.

Get in edit

Access edit

The site can only be accessed by boat. It is site is about 7.2km from the launch site at Mkomazi river mouth or 6km out from Scottburgh main beach.

Position edit

S30°15.864' E030°49.661' -30.264430.827681 Cathedral

This site is in a Marine Protected Area. A permit is required for access.

Understand edit

The stone arch at Cathedral

Depth edit

Maximum depth is about 29m. and the top of the surrounding reef is about 24m.

Visibility edit

Visibility may exceed 15m

Water Temperature edit

About 21°C

Topography edit

Cathedral is a big roundish hole on the northern seaward side of the shoal, featuring a rock bridge over one side. The hole is several metres deep and maybe 20m wide. Rocky reef to the north gets shallower in places.

Conditions edit

See edit

Moray eel

Paperfish

Peacock mantis shrimp

Spanish dancer nudibranch

Purple sea fan

Marine life edit

Various fish and reef invertebrates: Raggy or tasseled scorpionfish, Paperfish, Yellowmouth moray, Salt and pepper moray, Honeycomb moray, Goldie, Striped eel-catfish, Domino, Coachman, Emperor angelfish, Halfmoon rockcod, Whitespot butterflyfish, Clown triggerfish, Yellow snappers. Encrusting hard corals, Staghorn hard corals, Branched black corals, Red sea fan with purple polyps, Yellow whip coral, Branching soft corals, Green tree coral, Thistle soft coral, Striped and spotted anemone, Orange lacy false corals, Lacy white bryozoans, Dead man's fingers, Peacock mantis shrimp, Cleaner shrimps, Lobster, Blue-green sponge, Brown wall sponge, Grey volcano sponge, Yellow tip granular stars, Light brown starfish, Brown feather stars, Brown and orange spiky starfish, Nudibranchs, Spanish dancer. The site is regularly cleaned and surveyed by Crystal Divers as part of Project AWARE's Adopt a Divesite campaign.

Features edit

Big round pothole at the edge of the tabular reef, with a stone bridge on the east side.

Photography edit

When the visibility is sufficient in winter, this site allows good photography of sharks. The site is also excellent for macro-photography.

Suggested Routes edit

During winter do not only focus on the sharks. Observe all the other sea life around the site including shrimps, colourful nudibranchs and many fish.

Stay safe edit

Hazards edit

There may be sharks, as this is one of the main attractions of Aliwal shoal, but the Ragged tooth shark is not considered a significant hazard to divers if not molested or startled. During winter, several ragged-tooth sharks inhabit the Cathedral. Be careful not to startle, threaten or touch these sharks.

Skills edit

No special skills required.

Equipment edit

Conventional recreational dive gear is sufficient for diving this site. A DSMB may be useful if you have to ascend away from the dive leader.

Back to Diving Aliwal Shoal

This dive guide to Cathedral is a usable article. It has information on location and equipment as well as some complete entries on what to see. An adventurous person could use this article, but please feel free to improve it by editing the page.