

Best for intermediate divers, 15-25m, boat entry, mild current.
Outer Castle is a reef located 1900 metres offshore in the Roman Rock Area of False Bay. This boat-only dive site features depths ranging from 15 to 25 metres, with an average depth of 17 metres. Divers can expect mild currents, though surge and swell conditions vary. Visibility typically ranges between 5 and 10 metres. Marine life recorded at the site includes sea stars, klipfish, brittle stars, morwong, hottentot, and red roman. Rarer sightings include broadnose sevengill sharks, smooth rays, common octopus, long-nosed fur seals, pyjama sharks, flatworms, crayfish, and puffadder shysharks. Due to active boat traffic, the use of a surface marker buoy is essential for all ascents.
-34.23867, 18.48337
Check sea conditions and boat operator schedules locally before committing, as Atlantic swell can change quickly and affect both the crossing and conditions on the reef. Carry a surface marker buoy for every ascent given the boat traffic in the area.
The site is located 15 kilometres offshore and requires a boat for access.
Recorded at this site
Depth
15-25m
Visibility
5-10m
Skill Level
Intermediate
Entry
Boat
Boat required
Water Temp
14-17°C
Current
Mild
Typical Dive
50 min
Best Time
Aug, Sep, Oct
Divers may encounter sea stars, klipfish, brittle stars, morwong, hottentot, and red roman. Rarer sightings include broadnose sevengill sharks, smooth rays, common octopus, long-nosed fur seals, pyjama sharks, flatworms, crayfish, and puffadder shysharks.
The site is rated for intermediate divers. While open water certification is the minimum requirement, comfort in cold water and occasionally surgy conditions is recommended.
The reef depth ranges from 15 to 25 metres, with an average depth of 17 metres.
Outer Castle is a boat-only dive site located 1900 metres from the shore.
Water temperatures range from 14C to 17C throughout the year, requiring a well-fitted wetsuit of at least 5mm.
Diving at Outer Castle in Simon's Town requires the following certifications: Open Water. Always dive within your training limits.
A 7mm wetsuit or semi-dry is recommended for diving at Outer Castle in Simon's Town. Water temperatures range from 14°C to 17°C.
The best months to visit Outer Castle in Simon's Town are August, September, and October. Conditions outside these months can still be good but are less predictable.
Divers at Outer Castle in Simon's Town should be aware of sharks. These encounters are generally rare and avoidable with proper awareness. Follow local safety guidance and maintain a respectful distance from all marine life.