My weekends away usually involve a lie-in and a fry-up, not shivering at the edge of a lake at 8am, trying to find the nerve to jump in. But that’s the Fritton Arms’ USP: its extensive grounds encompass two-mile-long Fritton lake, and guests can join thrice-weekly open-water swimming sessions.

The swimmers at my Saturday-morning session look pretty serious, with wetsuits and talk of triathlons. But they welcome an ill-equipped interloper in a bikini, doing one lap of leisurely breaststroke to every three of theirs at a furious front crawl.

Once I’ve taken the plunge, I love it. The lake is a long, narrow S-shape with woods all around. The swimming area is marked out into a 100-metre warm-up length and longer routes, there are coaches and a safety boat on hand. Less serious swimmers can paddle along the banks and through reed beds, or just float about, looking up at the big Norfolk sky.

It is an invigorating start to the day – and works up a better appetite than lazing in bed. The hotel’s breakfast menu is appealing, though my English muffin with crushed avocado, kale, cherry tomatoes and poached egg is more successful than my partner’s rather dull potato and parsley frittata.

The Fritton Arms is a 16th-century manor house with nine bedrooms, and is part of the 5,000-acre Somerleyton Estate. In a feudal throwback, it is still owned by Lord and Lady Somerleyton, who condescend to allow commoners to eat, drink and sleep there (and pay them money, too, of course).

Downstairs is all wooden floorboards, beams and log fires, so many that the smell of woodsmoke is almost overpowering. It is all ultra-tasteful, with the odd outbreak of personality: one room is painted bright pink. Stephen, the director of hospitality, says they are aiming for a Soho Farmhouse feel.

Our room is large and light, thanks to the big bay window overlooking the parkland. Walls and fabrics are shades of white and grey, and furniture is traditional, but the headboard is a shocking orange print and competes with the orange and pink lampshades. The artwork is a fun mix: an abstract landscape, a nude, an incongruous pink shed. The bathroom is back to inoffensive – other than a note warning that guests will be charged 22 quid for each Cowshed product that they nick.

As well as swimming, the grounds offer walks, trail runs and horse riding, plus holiday cottages and, as of last summer, a campsite. Somerleyton Hall, the stately home, is open to visitors from April to September (Tuesdays, Wednesdays – gardens only, Thursdays and Sundays) – the history of the house is interesting and the gardens are delightful, supplying the gorgeous gladioli and other cut flowers in the hotel.

Hugh Crossley, the fourth Baron Somerleyton, also owns the Duke’s Head pub (a three-mile drive away, but a shorter walk when improvements to footpaths are made), where we have dinner on the first night. Locals squeeze into a small, happily ungentrified bar, while visitors from the hotel eat quail (£6.50) and lemon sole (£25.50) in the restaurant. Despite the slightly uncomfortable upstairs/downstairs vibe, the food is undeniably excellent.

We have dinner in the hotel on the second night, where the menu is chock-full of estate produce cooked in the wood-fired oven. Again, it is great quality, from a starter of scallops with cauliflower (£8.50) to the simple, seasonal desserts of poached pears and spiced plums (£6.50 each). The wine list gets top marks for including a Puglian red made from underrated aglianico, my new favourite grape.

Guests who tire of the estate have two counties to explore; Fritton is on the Norfolk/Suffolk border, seven miles from Great Yarmouth and 10 miles from Lowestoft. We spent an afternoon in the latter town, which is sadly rundown – it might be a better bet to venture further down the coast to pretty Southwold. And this is Broads country – but with an on-site lake, who needs the Broads? There are rowing boats, kayaks and SUPs for hire here for those who don’t fancy swimming, and for those who do, the season is no obstacle; the Saturday sessions run all year round. I recommend waiting until it’s warmed up a bit …
• Accommodation was provided by the Fritton Arms (doubles from £130 B&B, 01493 484008, frittonarms.co.uk). Open-water swimming sessions are £6 for 2½ hours, 8am-10.30am Saturdays (year-round), 5.30pm-8pm Tuesdays and Thursdays (25 April to 28 October).

Ask a local

Nick Lane, company director

• Walk and cycle

I like to walk parts of the Angles Way, a 93-mile path from Great Yarmouth to Thetford, and the Wherryman’s Way, a 35-mile route through the Broads.

• Eat
The Swan in Loddon serves local produce such as Ellingham asparagus and north Norfolk crab. Loddon is a beautiful Georgian market town.

• Art

Southwold Gallery has exhibitions of local artists, but if you’re looking for Picasso, Henry Moore, Antony Gormley and Francis Bacon then head to the Sainsbury Centre for Visual Arts in Norwich.