Conditions & tides
Scored by DiveConnect's site-physics model
Marine forecast via Copernicus Marine. Score is a rule-based guide from swell/wind vs. the site's exposure — always dive your own assessment.
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About this site
Porth Colmon is a small cove on the north coast of the Llyn Peninsula in Gwynedd, Wales, facing out into Caernarfon Bay and the wider Irish Sea. The surrounding coastline is rugged and rural, with access typically via the narrow lanes that run through the nearby farmland to the shore. The dive site here reaches a maximum depth of around 10 metres, making it a shallow entry into this stretch of the Llyn coast.
AI overviewMarine life here
Confirmed by our research team, reported by independent divers, or observed nearby via iNaturalist — each entry is labelled with its source.
Common Sea StarAsterias rubensReported here · unconfirmed
Dead Man's FingersAlcyonium digitatumReported here · unconfirmed
Rose Sun StarCrossaster papposusReported here · unconfirmed
Sea BeardNemertesia antenninaReported here · unconfirmed
Durable tips from divers — access, hazards, marine life, facilities. For day-of conditions, use the report tool in the conditions card above.
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