The hotel: first impressions are the ones that stick. I rounded a bend in the country road from Kirkby Stephen to be struck open-mouthed by the sight of turrets, towers, grey walls and windows rising from a sea of fiery-orange autumnal trees. Augill Castle, sunk in the rolling hill country where Yorkshire and Cumbria march together, is beautifully situated.

There’s absolutely nothing stuck-up or forbidding about this most laid-back of castles. As soon as I’d scrunched to a halt on the gravel in front of the building, Leighton, the Australian man-about-hotel, was out, shaking my hand and showing me round like a friend rather than a customer. “The fires are all laid, so light ’em if you’d like to. Help yourself to a beer — it’s an honesty bar. Holly, get down off that sofa!”

The castle is a Victorian folly, built as a weekend fantasy retreat in the 1840s by John Bagot Pearson, “a gentleman of leisure and considerable means”. Simon and Wendy Bennett bought it as a run-down mess in 1997; since then, they’ve dedicated their lives to creating a place that’s grand in design and conception (Jacobean oak panelling, huge fires, a gorgeous embossed dining room), but easy and informal in atmosphere (evenings in the music room, with Wendy banging the joanna; staff in jeans and broad smiles; no regimentation or set times for breakfast and check-out). A measure of the relaxed nature of Augill: noting that I was the only dinner guest, Leighton emerged from the kitchen with his own knife, plate and glass of wine at cheese time, to sit, snack and yarn with me.

What about the rooms? In each of Augill Castle’s eight bedrooms hangs a photograph of the state of the room in the early 1990s, before restoration. Mine, Langdale, looked like a builder’s tip back then. Since those days, it has been transformed, with big peach curtains, a fine brass bedstead, a creaky old wardrobe and a nice battered club sofa on which I could have watched telly if I’d wanted to. Big, bountiful beds ‘r’ us at Augill — one of the rooms incorporates a four-poster with an embroidered valance, while another houses a lovely old polished roll-end bed. There are also two self-catering cottages, sleeping four.

And the grub? “Of course, no trouble at all,” Wendy Bennett had chirruped over the phone when I’d asked her if I could order a weekday dinner — normally it’s weekends only. I dined in solitary state, all alone in the castle’s gilt-and-blue dining hall. Augill’s à la carte menu opens with such delights as mussels in filo pastry and blinis with caviar, before going on to local Dales lamb, baked halibut with cockle broth and chicken and fresh date brochettes. But I was more than happy with what the obliging Bennetts rustled up for me — a locally smoked breast of chicken, very positively flavoured, with green beans for crunchiness and spinach for ferric earthiness, followed by poached pears.

I need some exercise: Augill is heaven for outdoorsy people. There are great country strolls right from the front door (Simon and Wendy can point you in the right direction); the glorious fell walks of the Lake District are less than an hour to the west; the Yorkshire Dales National Park butts up against the castle on the east; and the Coast to Coast Walk, a superb long-distance trail, traverses Kirkby Stephen, six miles to the south.

Good for: lovers of the laid-back and genuinely friendly.

Bad for: devotees of the crisply formal.

Augill Castle, Kirkby Stephen; 01768 341937, www.augillcastle.co.uk. Doubles cost £140, B&B; a four-course dinner is £35pp (Fri, Sat, otherwise by arrangement; advance booking required). Self-catering cottages, sleeping up to four people, start at £400 for a minimum three-night stay; a week costs £560

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