Board a small boat from Porthkerris and head for the Mannacles, a famed granite reef off the Lizard Peninsula. Small groups, local timing for slack tides, and rich temperate marine life make each dive memorable.
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Difficulty
moderate
Duration
6–8 hours
Fitness Level
Be comfortable swimming in moderate chop, handling kit on a rolling boat, and completing two dives in cool water.
Wildlife
History
The Mannacles have long been a landmark for mariners and an established British dive destination, known for complex granite reef topography.
Conservation
Practice no-touch diving, pack out all litter, and follow local dive codes; timing trips for slack tides reduces unnecessary churn and habitat disturbance.
Karleyth Diving
Karleyth Diving is a dive operator based in Ruan High Lanes, England. The business runs a programme of SSI training courses, guided shore dives and snorkel tours for beginners, families and advanced recreational divers.
Offerings include SSI Open Water Course, SSI Advanced Course, SSI Deep Diving, Enriched Air Nitrox, Drysuit Course, Perfect Buoyancy, Diver Stress and Rescue, Scuba Skills Update and Try Dive sea sessions for first-time divers. Shore-based guided diving and shore diving packages focus on local coastal sites around Cornwall and remove the need for boats or strict timetables. Children's programmes include organised SSI Explorers Kids clubs available as full-term (12 sessions), half-term (6 sessions) and weekly options to suit family schedules.
Training and guided trips are run by SSI professionals and follow industry-standard safety and equipment procedures. The business emphasises flexible scheduling, clear certification pathways and practical in-water training to build diver confidence. Practical courses combine confined water sessions, open water dives and classroom theory where required, preparing students for independent diving and further specialties.
Karleyth Diving maintains a focus on environmental awareness and buoyancy skills that protect marine habitats while improving photographic opportunities. Booking information, course prerequisites and local site details are provided on request, allowing divers to prepare before arrival. For shore divers, snorkelers and families seeking SSI-accredited courses and guided coastal dives near Ruan High Lanes, Karleyth Diving provides a local, specialist option.
Contact details, availability and pricing are provided for each course to help customers plan bookings with transparent information and safety expectations.
Location
Ruan High Lanes
Cornwall shore diving base
SSI Training
Multiple SSI
Provider of SSI-certified courses
Kids Clubs
12 / 6 / Weekly
Flexible children's programmes
Trips Offered
17
Range of SSI courses & tours
Secure a spot on a Try Dive, Open Water course, specialty programme or family snorkel tour — check dates and availability today.
Book slack-tide slots early
Operators time trips around slack tides for best visibility and safety; secure your spot well in advance.
Bring thermal protection
Water is cold even in summer—insulated wetsuits or drysuits, hoods and gloves improve comfort and bottom time.
Mind surface intervals
Allow sufficient surface time between dives and use shore facilities to rinse and repack gear efficiently.
Pack a dive light and macro lens
Crevices and overhangs hold small critters; a torch and macro setup help you spot and photograph them.
Drysuit or thick wetsuit (7mm)
Cold Atlantic water around the Lizard demands strong thermal protection to stay warm and focused.
spring
Hood and gloves
Protect extremities from cold and abrasion while searching crevices.
Dive computer with depth tracking
Tidal sites require precise profile management and surface-interval planning.
Underwater torch and macro lens
Improve visibility in overhangs and capture small reef creatures in detail.