I should have known the sat-nav was up to no good when it tried to send me through a field near Amiens. Three hours from Calais, full of coffee and false confidence, I was already congratulating myself on finding this place when the tarmac ran out and a very unimpressed-looking horse became my audience. Reversing a hire car full of suitcases while maintaining some dignity is, I have learned, physically impossible. The horse knew it. I knew it. We shared a moment.

Bray Les Mareuil sits tucked into the Baie de Somme, that wide, watery stretch of northern France where the sky seems to start at shoulder height and keep going forever. The property itself is one of those solid Picardy houses, all sensible brick and shutters that actually close, with a garden that backs onto nothing much except fields and the distant promise of the bay. I arrived properly the second time, via actual roads, in a state of mild trauma and considerable wind-blown dishevelment.

The weather, naturally, had been waiting for me. Picardy does not do guaranteed sunshine. It does dramatic. My first morning dawned grey and spitty, the kind of drizzle that cannot commit to proper rain but will absolutely ruin your hair. I had packed with the optimism of a fool, one pair of walking boots and a cagoule that had last seen action on a Duke of Edinburgh expedition in 2003. The forecast, consulted over a cup of tea that tasted faintly of the ferry, suggested "clearing later." Reader, it did not clear.

I set off anyway, because what else is one to do? The path from the village towards Saint-Valery-sur-Somme follows the old railway line, flat and straight and entirely exposed to whatever the Channel feels like throwing at you. Within twenty minutes I understood why the locals had looked at me with that particular French sympathy. The wind came sideways. My cagoule achieved the remarkable feat of keeping nothing dry while simultaneously inflating like a parachute, causing a small child to point and what I choose to believe was delight.

I walked for two hours in conditions that would have had the BBC sending reporters to coastal locations. The bay itself, when I finally reached a vantage point, was extraordinary. The tide was out, revealing mudflats that stretched to the horizon, and somewhere in that grey-brown expanse seals were apparently loafing about. I saw none. I saw only rain, and my own stubbornness reflected in every puddle.

The return journey was worse, because I had convinced myself that a "shortcut" through the salt marshes would be quicker. It was not quicker. It involved a gate that did not open, a fence that definitely should not have been climbed by someone of my coordination, and a moment of genuine panic involving quicksand that turned out to be merely very enthusiastic mud. I emerged onto the lane behind the property looking like I had been excavated from a peat bog. The same horse, somehow, was there. Its opinion had not changed.

That evening I sat in the kitchen with the heating on full and a bottle of local Picardy beer, examining my ruined boots and my bruised pride. The weather had beaten me, fair and square. But there was something in that defeat that felt honest, properly earned. The bay had not performed for me. It had simply been itself, vast and indifferent and slightly damp, and I had been small and foolish and absolutely present in it.

The next morning, of course, the sun came out. I walked the same path in entirely different clothes, smug and dry, and saw the seals after all, and a heron, and the whole bay transformed into something almost too beautiful to bear. But it was the first walk I remembered. The one where the weather won, and I came back muddy and ridiculous and somehow more myself than when I had left.