Diving at Pyramid Rock reef and Shark Alley

Pyramid Rock reef and Shark Alley is an inshore rocky reef area in the Castle Rocks restricted area on the False Bay coast of the Cape Peninsula, near Cape Town in the Western Cape province of South Africa. It includes the dive sites Pyramid Rock, Shark Alley, and Castle Pinnacles.

Understand

See also: Diving the Cape Peninsula and False Bay#Understand

Map showing the dive sites at Pyramid Reef near Castle Rocks.

Pyramid is visible as a small spot of white water at the lower right centre of the aerial photo (CDS&M).

Pyramid Rock reef is the best dive site near Cape Town for variety of fish, and Shark alley, along its inshore edge, is the best site near Cape Town to see Cow sharks, although they have occasionally been reported from other sites in False Bay.

Position

• 1 Shark Alley: S34°14.21’ E018°28.60’— (Approximate) A mostly sandy bottomed site between Pyramid Reef and the shoreline reef between Rumbly Bay and Castle Rock.
• 2 Pyramid Rock: S34°14.225’ E018°28.700’ — Between Miller’s Point and Castle Rocks, a short distance offshore (about 250 m). It is always visible, either as pointed black rock above the surface or as a patch of white water at very high tide. On a very low tide there is another lower rock nearby which also breaks the surface.
• 3 Castle Pinnacles: S34°14.363’ E018°28.827’ — The south-easternmost part of the reef, bordering the outer end of the long sandy gully between Pyramid Rock reef and Castle Rock reef. Depth on the bottom is about 15 m, and the top of the pinnacle is less than 9 m deep.

This site is entirely inside the Castle Rocks Restricted Zone in the Table Mountain National Park Marine Protected Area (2004). A permit is required.

Name

The reef is named "Pyramid" for the pointed rock that marks the site. It projects above the water at all tides and is easily identified. The name "Shark Alley"refers to the Cow sharks Notorhynchus cepedianus frequently seen at the site, and the topography of the site, which is in the form of a relatively deep sandy bottomed alley between the shore and the higher reefs at Pyramid, a little further out. Sightings have declined considerably, possibly as a result of predation by orcas.

Depth

Maximum depth is at about 18 m in the Sansui Reef area to the southwest, and maximum depth of Shark Alley is about 12 m, with an average of about 8 m in the alley.

Topography

Large granite corestone boulders on outcrops with sand patches in deep areas and at the bottom of some gullies. There are several small tunnels, caves and overhangs. Further offshore there is sand bottom between the pyramid reefs and the Pie Rock and Outer Castle reefs. Offshore sand is pinkish and moderately coarse and even grained. Large inshore patches are of finer and whiter sand, particularly the sandy area at Shark Alley to the west and the sand tongue to the south which separates Pyramid reefs from Castle Rocks reefs. There is dense kelp forest on shallower rocks and near-shore reef.

Geology: Granite corestone boulders of the Pre-Cambrian Peninsula pluton, and wave rounded sandstone boulders from overlaying formations.

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  This view of the rock at Pyramid seen from Castle Rocks shows the reason for the site's name
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  High profile reef at Pyramid
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  Jutjaw over open reef
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  Hottentot seabream in kelp forest

Conditions

Usually considered to be a winter dive but there are also occasional opportunities in spring and autumn. The site is well sheltered from north west wind and chop. Swell from the south west or south east will cause surge. Judge by the conditions at the entry point and the colour of the water further out.

Facilities

Parking at the side of the road is not very secure, and you also have to take into account baboons, which may investigate your vehicle in the hope of finding food. Lock the car and put any valuables where they can not be seen.

Get in

See also: Diving the Cape Peninsula and False Bay#Boat dives

The site may be dived from shore or boat.

Shore entry: Parking at the side of the road. The usual entry point is at a small rocky beach just inshore of Pyramid rock and north of Castle Rocks at a position along the shoreline at S34°14.288’ E018°28.537’. Check out the pathways leading down to the shore before kitting up, as some are worse than others. All are steep and slippery when wet, some are dangerously so. The shore entry is over some small rounded boulders on the beach, and bigger ones in the water, and can be a little tricky if there is a swell, as this results in a small shore break which can be troublesome if you are carrying a large camera with strobes.

Alternative shore entry from Castle Rocks north entry at S34°14'19.98" E018°28'35.92"

Another alternative shore entry is from Rumbly Bay. Entry at the old slipway at the Cape Boat Club. This access can be risky if the slip is in use. Keep a good lookout for boats being launched or recovered, they may not be able to keep clear of you, as the channel is narrow and shallow, with rocks and heavy kelp to both sides, and swell and cross winds to contend with, so stay well away from them and out of the boat lane. The route is either around north of the exposed rocks, along the edge of the boat lane, then follow the edge of the kelp until you are in the alley, or cut through the gap south of the exposed rocks, which is much safer, as boats do not go there, but more effort, as the kelp is heavy, and navigation is by compass. The slipway can be very slippery due to algal growth below the high tide mark.

Boat dives at this site are popular as many divers do not like the shore access, particularly when carrying cameras. Boat access requires care due to the kelp forests offshore of the site. There is a sandy gap between the north side of Castle Rocks and Pyramid which extends near to the shore and which is relatively clear of kelp, and the site can also be approached from the north east through an area with sparse kelp, which is the far north part of the alley. This does not appear to bother the sharks. The site is approximately 1.9 km from Miller's Point slipway and 9.1km from Simon's Town jetty.

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  Shark Alley entry point. Pyramid is the small pointed black rock in the middle background. Shark Alley is beyond the inshore kelp and to the left, running approximately parallel to the shoreline.
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  Entry area for Shark Alley and Pyramid. Choose between the flattish rock to the left and one in the middle of the picture.
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  The boulders indicate the roadside parking nearest the path to the entry area

Do

Dive at one of the listed drop points and explore the vicinity, or follow one of the suggested routes

1 Shark Alley: S34°14.21’ E018°28.60’— (Approximate) A mostly sandy bottomed site between Pyramid Reef and the shoreline reef between Rumbly Bay and Castle Rock. Big granite boulders and outcrops with sand patches. Fairly dense kelp forest on the reefs on both sides, and more sparse kelp on the rocks in the alley. The south end of the alley has many fairly large boulders, and lots of smaller boulders and outcrops with occasional sandy gaps. Further north it opens up with larger sandy gaps until there is more sand than rock. The rock outcrops in this area are like small islands in a sea of sand. The sand is coarse and clean and light. This sand patch extends a considerable distance to the north east, getting wider the further you go. The sharks seem to favour the south end of the alley, or it may be that because it is narrower, they tend to be more easy to find there as they cruise up and down the alley.

2 Pyramid Reef East Pinnacles: S34°14.220’ E018°28.810’ — A shallow area of small pinnacles northeast of Pyramid Rock.

3 Pyramid Rock: S34°14.225’ E018°28.700’ — Between Miller’s Point and Castle Rocks, a short distance offshore (about 250 m). It is always visible, either as pointed black rock above the surface or as a patch of white water at very high tide. The rock itself is unmistakable and easy to identify as it extends above the surface at almost all states of the tide. The area has a number of huge boulders forming overhangs, gullies and the occasional small swim-through. To the north, the reef is lower and flatter, with fairly large open areas, and to the east it is largely unexplored.

4 Castle Pinnacles: S34°14.356' E018°28.826' — A group of fairly tall pinnacles along the edge of the sand. One of them has a large swim-through under it. To the northwest of the point at Castle Rocks across a sand tongue from the Castle Rocks reef, there is an area of large boulders and pinnacles. The pinnacles rise from a bottom of about 15 to 18 m, and in one case to within 3 m of the surface, and are huge sheer sided boulders. There are two major groups, the first one is a single large block with a crack along the middle. The second, in line with the first, but further out, is a jumble of rocks with caves, gullies and overhangs. There are more pinnacles further out, but they are not as high. One of these pinnacles has a double swim-through under it. Originally they were considered part of the Castle Rocks reef area, but they are separated by a stretch of sand, and are actually part of the Pyramid reef area.

5 Sansui Reefs: S34°14.35?’ E018°28.84?’ — (approximate) An area of picturesque small ridges and boulders on a rippled white sand bottom near the Castle Pinnacles. Quite picturesque in good visibility, and reminiscent of the Japanese gardening style after which it was named.

Routes

Pyramid: There are no good areas for anchoring. Any place close to the pinnacle is likely to foul the anchor and damage the reef life. A shotline is also not necessary or desirable for ordinary recreational dives.

1. Entry at North access point at Castle Rocks, Surface swim to the pyramid rock. Descend and circumnavigate the pinnacle, compass course back to Castle Rocks about SW (225° magnetic).
2. Entry at North access point at Castle Rocks, descend and swim north-west over the sand to the reef to the north, Follow the south edge of this reef eastwards to the pinnacles.
3. If you go beyond the pinnacles with the reef edge to your left, you will get to the Sansui Reefs.
4. Alternative entry at Shark Alley entry, surface swim to the Pyramid rock and dive around it. To get back to the entry point, swim on a bearing of roughly east to north east magnetic and if you come to the sand patch, follow it in (about 320° magnetic). If you surface north of the entry point, there is a very rocky area which should be avoided if possible. Try to get back under water to stay under the kelp canopy if your air supply allows.
5. Alternative entry and exit at Rumbly Bay slipway at Miller's Point. Swim out around the big exposed rocks, descend and swim a compass course towards Pyramid. The reef gets better as you move south.

Shark Alley: The dives at this site involve getting to Shark Alley, and hanging around waiting for sharks. You can find sharks by looking for them, but you will see more fish if you wait quietly at a suitable place, and the sharks will come to you. They seem to like a close view and in some cases will pass within arms reach. It has never yet been necessary to fend them off. If you swim towards them they will usually swim away, very quickly if startled.

Shore dives: Entry at rocky shore below the road north of Castle Rocks point. There is a large flattish sloping rock which is good for exits and for entry if the tide is high. At low tide enter slightly south of this point where the kelp is most open. Surface swim about 80m through the kelp to the gap between the inshore forest and the Pyramid reef forest. Descend and work your way north and back and forth between the kelp forests. If you find a large relatively isolated rock with small bare rocky patches at its base, this is a good place to wait for fish. The alley is a bit over 200 m long.

If you swim below the kelp to get to Shark Alley, use a course of about southeast magnetic, follow the southern edge of the kelp for about 80m and turn northeast when you come to a group of rocks with kelp on top extending a bit to the south into the sand tongue. It may be necessary to surface to see where you are, as there are few easily recognisable landmarks. Those which may help are sand patches, relatively sparse kelp and a sudden increase of height of the rocks on the far side. There is a boulder pinnacle of moderate size in the alley which is close to the southern end. Sharks and other fish are often seen in this area.

Boat dives: Adapt the route to suit where the boat drops you off.

See

Marine life

See also: Diving the Cape Peninsula and False Bay#The marine ecology

Pyramid Rock: This is a very good site for fish, particularly on rebreather, as it has been a sanctuary for many years. This is a site where you may see Red steenbras, Red stumpnose, Bank steenbras, Janbruin, and Galjoen as well as the more common species like Hottentot, Roman, Jutjaw, Blacktail, Steentjies, Fransmadam, Two tone fingerfin, Redfingers and Strepies, and some of the common local Klipfish species. Cow sharks, Spotted gully sharks, Striped and Leopard catsharks and Puffadder shysharks may also be seen. There is kelp forest all round the site, and various seaweeds, particularly in the shallower areas and tops of rocks. There is also a large diversity of invertebrates.

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  Deepreef klipfish
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  Cape knifejaw
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  Juvenile Cape knifejaw
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  Cow shark
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  Mixed shoals of smaller fish
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  Cape triplefin
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  Shoals of 30 or more Galjoen have been seen here
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  Roman seabream
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  Red stumpnose
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  Pyjama shark

Shark Alley: There are extensive kelp forests of sea bamboo, and a relatively large variety of fish may be seen, the most prominent being the Cow sharks, but Spotted gully sharks, Red steenbras and Bank steenbras are also seen here. Cow sharks appear to favour this site, and there is a significantly better chance of finding them here than any other known site in this region. Multiple sightings are common, and there have been occasions when four or more Cow sharks have been in view simultaneously.

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  A Cow shark at Shark Alley
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  Cow sharks are unusual in that they have seven gill slits and only one dorsal fin, set far back. They can not be easily confused with any other shark.
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  This is one of the few places you have a reasonable chance of seeing a Red Steenbras

Photography

Pyramid is a good site for fish and macro photography. If you want to use flash, use an external strobe to reduce backscatter.

Shark Alley is a good site to photograph sharks. Water clarity is seldom more than 8 to 10 m, and often less, and particulates will cause backscatter, so ambient light is often used. However the sharks will often approach very close to the diver, so wide angle lenses can also be useful.

Stay safe

See also: Diving the Cape Peninsula and False Bay#Stay safe

Hazards

The shore access can be tricky in a surge, particularly the exit, and technically the Cow sharks may be considered a hazard, as they are large and have cutting edged teeth as they feed on seals. This does not stop many divers.

There are groups of people who prowl the parking areas of this site on the main road. They have broken into several cars, and stolen either contents or the whole vehicle. It would be prudent to get someone to watch the car or hire a car guard. Also don't leave your car with valuables visible through the windows.

Wild baboons in the area will enter cars to look for food - do not leave your car doors open even if there is no food inside, even while you are near the car unless you are at the open door. Some of them know how to open an unlocked car door, so even closing the door is no guarantee that they will not get in and trash your loose goods.

Skills

No special skills required. A good site for the fit and competent snorkeller. A reasonable level of fitness and agility is required for the shore entries. There is a moderately long swim and a climb up to the road.

Equipment

See also: Diving the Cape Peninsula and False Bay#Equipment

A light is useful to see into holes and overhangs. A compass will help keep your bearings and let you navigate back to shore under water. A surface marker buoy is not recommended as it will get caught up in the kelp.

Nearby

• 1 Miller's Point tidal pool
• 2 Murphy's
• 3 Boat Rock
• 4 Festival Pinnacle
• 5 Fan Reef
• 6 Phone reef
• 7 Super Fan Reef
• 8 Outer Castle
• 9 Giant's Castle
• 10 Zigzag Reef
• 11 North Pie Rock Reef
• 12 West Pie Rock Reef
• 13 Castle Rocks Point Reefs
• 14 East Pie Rock Reef
• 15 South Pie Rock Pinnacles

Back to the Alphabetical list of sites, or list of dive sites in the Castle Rocks area

Other regional dive sites:

• Dive sites of Table Bay and approaches,
• Dive sites of the Cape Peninsula west coast
• Dive sites of False Bay offshore and approaches
• Dive sites of False Bay east coast
• Fresh water dive sites of the Cape Town Metropolitan Area