Castor Rock

Diverse granite reef with pinnacles, gullies, and abundant invertebrates.

Boat Access
15m Avg Depth
22m Max Depth

About this dive site

This dive site, known as Castor Rock, is located on SA Navy charts. It’s a substantial granite reef featuring a diverse underwater landscape. The maximum depth varies across the area, reaching approximately 22 meters in the north and 18 meters in the south, with the highest point of the reef rising to around 7 meters. The reef is divided into two lobes by narrow sand tongues that intersect near Wonders Pinnacle. The topography includes moderate to low outcrops, occasional high areas, small gullies, ridges, boulders, crevices, and overhangs. Sandy bottomed gullies penetrate the reef edges at irregular intervals.

The marine life is abundant and varied. You'll find a wide array of invertebrates, including numerous red bait ascidians, encrusting sponges, and corals like bushy corallines and coral placomium. Large shoals of fish such as Hottentot, Galjoen, Dassie, and Fransmadam are frequently observed near the pinnacles. Bank Steenbras are also present, though typically smaller in size. Elegant feather stars are scattered throughout, particularly on steeper slopes, alongside common feather stars and clumps of red-chested and mauve cucumbers, striped anemones, and various types of sea fans – palmate, sinuous, and flagellar varieties are all relatively common. Golden sea cucumbers are abundant along the reef slopes and in the sand margins, while occasional virtual carpets of hairy brittle stars can be spotted at the north end. The site offers good photographic opportunities, although visibility may vary depending on conditions.

Diving Freediving Snorkeling

Site Ratings

Big Marine Life Good
Macro Marine Life Excellent
Landscape Quality Excellent
Water Visibility Good Viz
Famousness Well Known

Plan Your Visit

pinnacleboulderswide anglemacro photographyabundant fish lifeinvertebratesgranite reef

Marine Life

HottentotGaljoenDassieFransmadamBank Steenbrasred bait ascidiansencrusting spongespalmate sea fanssinuous sea fansflagellar sea fansred-chested cucumbersstriped anemoneshairy brittle starsgolden sea cucumbers

Things to Note

Difficulty:

Intermediate

Variable depths (7-22m) and complex reef topography suit experienced divers, but can accommodate beginners with a guide.

Hazards:
depthboat trafficvariable visibility
Current Strength:

Variable

Diving Conditions

Water Temperature Now: 14.1°C

Wind

Tide

Swell

Swell Height (m)
Swell Period (s)

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