I don’t remember when I first heard about Frenchman’s Creek. Not Daphne du Maurier’s pirate romance, but the house of the same name near the Helford River. An old stone cottage, the colour of clotted cream, that hides in the woods by a burbling stream. Perhaps I dreamed it? I stayed once, one winter, but still sometimes wonder if it actually exists.

This corner of Cornwall has that place-out-of-time feel. Unlike the brazen drama of the wave-smacked coast, there’s a peace and a secrecy to the Helford River. Once a bustling highway, now this sinuous passage is left largely to the ancient oaks, the prehistoric herons and the ghosts of smugglers’ ships – the kind that inspired du Maurier, who honeymooned there. This feeling is even more palpable in winter, when the grockles have gone and the ferry – there’s been a crossing at Helford for at least 1,000 years – is anchored for the season.

Frenchman’s Creek isn’t even on the main river. It sits on a trifling tributary of the same name. By the time this inlet reaches the cottage, it’s a brush-tangled slip of a thing, trickling over cracked slates, beneath fern-frilled trees.

The house was built for a labourer or boatman in the early 19th century. In the 1930s, it was rented for “picnics and day pleasures” by a lady called Clara Vyvyan. She wrote about it in her book, The Helford River: “Sometimes Maria and I would meet there in the winter … and we would sit over the fire talking at leisure about this world and many others. Or I would go down there alone, kindle a fire … enjoy complete solitude. Often, instead of reading, I would sit gazing out of the window at that wall of trees rising to the sky and feeling the quiet of that place as if it were soft music.”

I have a December birthday and the husband and I like to get away; to find somewhere for such “day pleasures” as the light and weather allow, somewhere to hunker down if they don’t. Frenchman’s Creek – restored and rented by the Landmark Trust – was just that. Cobweb-blasting walks on the doorstep, a wood burner by which to huddle.

We arrived there in the gloaming, a hair-raising affair: the track – could this really be it? – plunging steep and slippy from the road. We were relieved to park, walk the rest, the cottage only revealed at the last moment, as if desperate to stay hidden. We pushed the mossy gate, unlocked the deep-red door, felt the magic, stepped inside.

There was no TV. We had no signal. The furniture was neat but simple. I didn’t ever want to leave. My husband had booked a meal at a smart restaurant in Falmouth. Very kind, I said, but could we stay in instead? So we fried up a sort of bubble and squeak, fought over the best burnt bits, drank red wine, wondered: if the world ended, would we even realise?

We did eventually venture out. We followed the path along the creek – our creek – to the river, to reach Helford village. Though the cottage seems marooned in a faraway land, it’s only a mile walk from this cluster of whitewash and thatch, and the cosy Shipwrights Arms. We ate crab sandwiches in Mousehole, where the harbour was being strung with its annual Christmas lights. We also walked a coast-path loop of the Lizard; Kynance Cove, so packed in summer, was wave-wild and empty, while a mini murmur of starlings bulged and twirled in the gunmetal sky.

And when our cheeks were ruddy and our lungs refreshed, we returned to Frenchman’s Creek, its soft music calling us home.

Frenchman’s Creek (landmarktrust.org.uk) sleeps four, from £396 for four nights