Nearly every spa now has its own website - a far cry from the paltry coverage of a couple of years ago - so there is plenty of opportunity for comparison.
Excellent international directory of spas, listed by country and US state. Over 100 day spas in New York, including the fashionable Bliss (Blissworld).
The British Spas Research Directory
A highly customised search: choose whether you want a single-sex spa, and specify the kind of water it offers, the treatments available, the ailments it specialises in, etc.
A more upmarket worldwide directory of costlier spas: Champneys, Cliveden, Evian and the like.
The Mountain Lodge and Spa at Delphie
A large and successful spa located in County Mayo. See also the five recommended Irish health farms linked from healthfarmsofireland.com.
A four-star spa emporium near Marseille favoured by French celebrities and football teams. Luxurious and costly.
Gamble by night and burn money by day at one of Las Vegas's 24 spas.
French site promoting 80 seaside spas specialising in thalassotherapy - the use of seawater, and often seaweed and mud, to promote health. If you don't read French, try Thalassa, which explains the more arcane treatments - the reaching 50 cure, the leg-muscle cure - in considerable detail. Centres in Morocco, Sardinia and Portugal are included and can be booked online. For further listings, Franceguide.
My Switzerland
If you prefer mountains and inland springs, Switzerland has dozens of hydrotherapy centres, as does Germany (deutschland-tourismus.de/e/7807.html).
Mother-and-baby stays "to rediscover your fitness after giving birth" cost £370 for a week. Twenty-eight sessions of "tranquil" spa treatments over six days are £280.
In a year's time, the new Bath spa will reopen. Bath hopes to regain the reputation it acquired in the late 18th century.
Annual membership of the Covent Garden spa starts at £1,260, but an evening costs £40 and a full day £60, making it a possible birthday or Christmas present. The site itself is superb.
