Mount's Bay and the Longships are far astern, and the sea shines a deep and kindly blue, with an oceanic heave and a couple of dolphins. The picture on the plotter is less kindly. This is the Bristol Channel, a sea area just about the same shape and sometimes just about as welcoming - as the mouth of a blunderbuss. A westerly gale here has the unpleasant habit of veering northwesterly, making the ironbound coast a lee shore. The wheel kicks under the hands, and the boat tears northeast.
The weather today is northwesterly but civil. The cliffs of Penwith slide by, and St Ives Bay opens to starboard. No ice creams or art galleries today, though. We have a knot of tide under us, and a fair wind, and it is a good idea to maintain a bit of offing here, as between St Ives and Trevose Head there is no shelter to speak of.
Beyond Trevose Head is the Camel estuary. Cross the Doom Bar within two hours either side of high water, and into beautiful Padstow harbour, everything a Cornish harbour should be, gated for the boat, pubs and restaurants for the crew, buckets and spades for the junior members.
Next morning it is time to leave, motoring out of the flat blue Camel, hoisting sail by the swells creaming in rocks off Pentire Point and setting the nose for the grim hunch of Hartland some thirty miles of unlit cliff northeast.
It is some forty miles between shelter and shelter, so it is a relief to round into Bideford Bay, the whaleback of Lundy Island rising grey to the northwest, encouragingly tall: Lundy high, sign of dry.
The wind has dropped, and the forecast is talking about southeasterlies. Down plunges the anchor off Clovelly, queen of ancient fishing villages, where they still net herring under sail; down come the sails, and down goes the sun.
The Bideford Fairway buoy flashes white all night. Ignore its seductions (and the evil bar it marks) and press on. The water has turned from clear oceanic blue to jade-green, and the tide is running at three knots, sweeping us past Ilfracombe and a handful of anchorages to Lynmouth, then the minute basin of Porlock Weir and the wigwams of Minehead.
The jade-green turns to mud-brown, freighted with Welsh soil washed down the mighty Severn – Watchet's charming marina needs perpetual dredging. As the muddy pills and creeks of the shore fly by, both banks of the waterway are visible, the tide compressed to six knots and more, and at nearly ten metres the world's second-biggest range. Anchor in the muddy eddy off Portishead and wait for a fair tide up the Avon to Bristol.
We could sail up the Severn under the motorway bridges on the last of the tide, drop in at Lydney, lock into the Sharpness Canal and cruise on fresh water to the port of Gloucester and far into the heart of Britain. But the weather is still southeasterly, so it would be folly not to carry the racing ebb down to Cardiff and lock through the barrage into the enormous Bay.
Next morning it is time to head west past Barry Docks and Porthcawl - once drying, now gated – along the Glamorgan shore. The grim furnaces of Port Talbot rise, and Swansea sprawled in the bight of its bay. But the white tower of the Mumbles light stands to starboard of the forestay. Carry the tide past the wild and beautiful Gower peninsula, riding the inshore venturi of Helwick Pass to the lonely anchorage tucked behind Worms Head.
Eat dinner watching the sun sink over Carmarthen Bay. The complicated sandbanks and channels leading up to Burry Port, and further west the Towy, treacherous and romantic as piracy. At the bay's western end is Tenby, and just offshore the calm monastic retreat of Caldey Island.
The wind holds. Head west to St Govan's Head to fish on the edge of the tide. To the north, the vast shapes of tankers creep towards the oil and gas terminals of Milford Haven; and beyond the tankers, the grey loom of islands.
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