This exclusive and beautifully appointed hotel has a spa to match, where traditional Cotswold stone is juxtaposed with sleek glass and stylish fixtures and fittings to stunning effect. Facilities include a hydrotherapy pool and six treatment rooms. A day spa package is available for £89, which includes a treatment and a two-course lunch, but you can also just pop in for a facial.
Treatments at Bliss are consistently good: efficient, long-lasting and featuring its excellent own-brand products. While there are longer, more relaxing body treatments to be had, Bliss is best for double-quick pedicures and manicures. Sit in line in your lunch break, put on headphones and settle back to watch telly.
Cowley Manor is a delectable blend of modern innovation in a period setting. Its spa illustrates the contrast perfectly, with its indoor and outdoor pools, steam room and sauna, and aromatherapy-inspired treatments. The signature treatment is a swoon-inducing mixture of acupressure, aromatherapy and reflexology. Spa facilities are reserved for overnight guests over the (busy) weekend, but day-trippers are welcome in the week.
Cowley Manor Cowley, near Cheltenham, Gloucestershire GL53 9NL (01242 870902/www.cowleymanor.com).
A private member's club and hotel, Babington naturally has its own spa (for overnight guests only). Housed in what was once the Georgian pile's cowshed, these days you'll find indoor and outdoor pools, steam, sauna and aroma rooms and nine lakeside treatment cabins, where lashings of the luscious in-house product range are administered.
You don't have to be a guest to visit One in Edinburgh's Sheraton Grand hotel. An ESPA spa (both in the products used, and the company that designed it), its marine algae and Oshadi clay body wraps are blissful; the pool complex and thermal suite are the real draws though. Cleopatra baths (minus the ass's milk), an infinity hydropool and 62-foot ozone swimming pool are complemented by the Celtic- and Roman-inspired laconium, tepidarium and aroma grotto.
One Spa8 Conference Square, Edinburgh EH3 8AN (0131 221 7777/www.onespa.com).
6. Pennyhill Park
Size is everything at this swish hotel spa, which extends over 45,000 square feet. There are eight pools, the largest of which, the 'ballroom pool', even has piped music underwater. 'Thermal heaven' doesn't stint either; its 11 rooms include a tepidarium and an ice cave (to boost your circulation).
In the 21 treatment rooms, expect lengthy and blissful rituals to complete the cosseting. You can also sleep over if a day trip seems too energetic.
Seaham Hall is just 20 minutes from the bustle of Newcastle, although you'd never know it at the hotel's adjoining spa. Open to non-guests, it's an oasis of oriental calm and quietude. In addition to the 45-strong treatment menu is a limestone hammam and Canadian redwood sauna and, to cool off, an ozone-cleansed pool that boasts secluded woodland views.
Another faultless ESPA spa within a hotel, many of the luxurious treatments here are inspired by the ancient Indian principles of Ayurveda. Day visitors must book treatments for a minimum of two hours; arrive early if you want to take advantage of the various heat and relaxation facilities, which include a large pool, a crystal steam room and a jacuzzi.
SequoiaThe Grove, Chandler's Cross, Hertfordshire WD3 4TG (01923 807807/www.thegrove.co.uk).
9. Chewton Glen
The famously plush spa at Chewton Glen has no shortage of facilities, including an ozone pool, hydrotherapy pool and ten treatment rooms. High-tech Linda Meredith treatments using collagen and oxygen feature on the skincare menu, while the body is buffed and polished with Molton Brown products. A wide array of 'spa day' packages are available, including an evening of pampering for those forced to work a nine to five. If you've got more time, check in to the hotel for the night.
It's hardly a cheap option (rituals of 120mins start at £250), but the level of soothing luxury at the Mandarin Oriental's spa justifies the expense. Day guests must book ahead; staff recommend arriving 45 minutes before your treatment to make use of the heavenly heat and water features, including an amethyst crystal steam room and Zen colour therapy area.