North Cornwall Heritage Coast, Cornwall, England
North Cornwall's Atlantic cliffs are spectacular but unforgiving. Merlin's Cave floods with the tide, Tintagel's island path can be dangerous in wind, and Boscastle's harbour is tidal. CoastMetric gives you all the data in one visit score.
About Tintagel & Boscastle
CoastMetric is a real-time conditions app for the Tintagel and Boscastle coastline — North Cornwall's most dramatic cliff scenery. Check live weather, Atlantic swell, tidal conditions and coastal path safety before visiting Tintagel Castle, Merlin's Cave or the South West Coast Path.
North Cornwall's slate cliffs are subject to sudden cliff falls and powerful Atlantic groundswell. Merlin's Cave is inaccessible and dangerous at high tide and in any swell. Boscastle Harbour floods in extreme rainfall. Path edges near the cliff top can be unstable.
Walking Routes
Check the live Visit Score before you set out — conditions here change fast.
The full South West Coast Path section between the two headlands — one of North Cornwall's finest walks. Steep ups and downs throughout; allow extra time. Return by local bus or taxi.
Tintagel Castle island (English Heritage entry charge), Merlin's Cave at low tide, and Rocky Valley with its ancient labyrinth carvings. Family-friendly with shorter distances and multiple points of interest.
Plan Your Visit
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Key Features
English Heritage site on a dramatic sea-stack island — legendary birthplace of King Arthur. Entry charge. New footbridge (2019) provides access to the island ruins.
A sea cave that runs through Tintagel Island — accessible at low tide only. Home to Merlin in the Arthurian legends. Dangerous — never attempt in any swell or above mid tide.
A narrow S-shaped inlet cut through black slate cliffs — one of the most dramatic harbours in England. Devasted by flash flood in 2004; rebuilt by the National Trust.
Two Bronze Age labyrinth carvings cut into the rock face in a hidden wooded valley — possibly 4,000 years old. Free access; just off the coastal path.
Live Data
All data is fetched from authoritative UK sources and recalculated every few minutes.
Safety Information
Merlin's Cave (below Tintagel Castle) is ONLY safe at low tide in calm sea conditions — waves can surge without warning. The Tintagel Castle island path is exposed to Atlantic wind — allow English Heritage staff guidance. Rocky Valley and St Nectan's Glen paths can be slippery after rain. Always check the tide forecast before planning beach access in coves.
All data, scores and recommendations are for informational purposes only. The Visit Score is an algorithmic estimate — not a substitute for your own judgement, local signage or official guidance.
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