USP A serious destination spa in the heart of Sussex that has nearly as many treatment rooms (25) as bedrooms (38) – and some of the latter have spa suite bathrooms with fancy walk-in three-way showers and a tub for two.

On a practical note, the spa hands out good-grip plastic sandals rather than the usual flimsy cotton footwear that gets soggy and increases the risk of slipping and breaking your neck.

AMBIENCE Utopia has learnt lessons from the layout at award-winning sister hotel spa Rowhill Grange in Kent. A slate trough fountain marks the glass-door entrance to a spacious reception area linked by French doors to a courtyard and brasserie.

Lifts from the bedrooms bring you directly to the reception lounge, which is roomy enough to find a quiet niche but not so grand that you feel forgotten. Its red velvet footstools, box sofas, mellow Farrow & Ball shades and bold graphic print wallpapers give it a lift above the average smart health club. The relaxation room has wavy leather lounge chairs in Le Corbusier style. The swirling staircase in the middle leads up to treatment rooms with names such as Enlightenment, while another takes you down past a reclining statue of Isis bearing water and fruit (surely the two symbols of the spa kingdom) to changing rooms and other wet facilities.

If the changing rooms led nowhere you wouldn’t feel short-changed – both the male and female versions have a sauna, steam room, funky showers and big lockers. The Saturday morning that I visited the whole marble-clad changing room was empty - it felt like a Roman emperor's domain.

Next door is a subterranean water-world – with alternating coloured back lights – and a nexus of Doric-style pillars around still and bubbling pools. Shelley, a big fan of the classical world and whose family once lived at Alexander House, might not have approved. The lack of daylight makes it the sort of place that’s good to retreat to on a winter’s day - emerging from here to brave the 20 landscaped yards to the outdoor hot tub leaves you feeling a bit discombobulated like coming out of the cinema during the daytime.

The main building is an old 17th-century mansion with a modern extension. Our room overlooked the outdoor hot tub and a plot of mobile homes. So far no night flights from nearby Gatwick have been misguided by the stretch of ground spotlights that mark out the route to the hot tub.

QUALITY OF EXPERIENCE The all-over orange and oat scrub was vigorous and abrasive but not invasive and left the skin feeling very soft. My therapist Scarlett - one of 20 mainly English therapists at Utopia - made light work of “hypnotising” me into a sleepy torpor by gently massaging my temples and cupping hands soaked in citrus and lavender oils just inches from my nose. Before that we engaged in a dose of interactive stretching and breathing, which made me feel like I'd done my bit for the day before settling into the remaining 45-minute Serenity body massage. Utopia uses natural Zing and Guinot products. A good range of fitness classes, from Sculpt and Tone to Power Chiyoga, runs all week in a smart studio-gym.

FOOD AND DRINK During the daytime you can wear your robe in Reflections brasserie, which has olive trees and an open fire in the courtyard, and provides a nice haven when the sun shines. The brasserie has those over-sized Pizza Express style menus and serves quite hearty catch-all fare - though for dinner I had bland scallops and tomato slices topped with dried herbs; for breakfast, salty porridge, OJ that tasted like squash and smoothies in a bottle. The afternoon tea tier looked fit for the estate’s forefathers and, while not the most technically accomplished dish, the fruit salad was a varied and colourful masterpiece.

IN CROWD Euro couples, stopovers from Gatwick and dirty weekenders cleaning up their act, as well as the usual crop of women with and without partners, many on day spa options.

WALLET WATCH One-night spa escape packages from £185. Relaxation days from £89 for a half day to £295 for the Ultimate experience. Oatmeal and Orange Treat is £36 for 25 minutes and the Serenity massage is £60 for 55 minutes.

NEED TO KNOW Alexander House Hotel, Turners Hill, West Sussex, RH10 4QD (01342 714914; www.alexanderhotels.co.uk)

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