Karleyth Diving’s SSI Open Water Course in St Mawes provides a solid foundation in diving through balanced theory and ocean practice. Learn essential skills while immersed in Cornwall’s striking underwater landscapes.
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Difficulty
moderate
Duration
3–5 days total
Fitness Level
Moderate fitness needed; ability to swim and tolerate cold water comfortably is important.
Wildlife
History
St Mawes harbour has been a protected anchorage since medieval times, hosting fishing fleets and naval patrols.
Conservation
Local dive operators promote responsible diving practices to protect fragile kelp beds and marine habitats.
Karleyth Diving
Karleyth Diving’s SSI Open Water Course in St Mawes provides a solid foundation in diving through balanced theory and ocean practice. Learn essential skills while immersed in Cornwall’s striking underwater landscapes.
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.
Check Weather and Tide Times
Proper planning around wind and tides is crucial for safe open water sessions in St Mawes’ coastal waters.
Use a Fullly Fitted Wetsuit
The waters can be chilly even in summer—wear a wetsuit to stay comfortable throughout dives.
Hydrate and Rest Well
Diving requires physical and mental alertness; stay well-hydrated and rested before each session.
Practice Skills Thoroughly in Confined Water
Mastery of basic skills in the pool or confined water area sets the stage for safe ocean dives.
Full-length wetsuit
Protects against cold water and abrasions during dives.
spring|summer|fall|winter
Mask and snorkel
Essential for surface swimming and underwater navigation.
Dive computer or depth gauge
Helps monitor depth and dive time for safety during open water sessions.
Dive boots and fins
Boots protect feet in rocky areas; fins provide efficient propulsion underwater.