Termas de Puyuhuapi, Chile
The spectacular landscape draws visitors to this corner of southern Chile, while the natural 40C hot springs entice them to this Patagonian spa resort. After the five-hour boat ride from Puerto Chacabuco you may well be in need of a soak and a massage. Once you've been pummelled and pressed, you can take a boat trip to the San Rafael glacier, hike through temperate rainforest, or kayak around the neighbouring islands.
Termas de Puyuhuapi, Bahia Dorita Canal, Patagonia, Chile (00 56 67 325 103). From £662 per person full-board, through Exsus (020-7292 5050; www.exsus.com).
Hotel Therme Vals, Switzerland
A bunker-like block of rock made up of 60,000 slabs of Valser quartzite may sound cold but, with water of up to 42C to dip into, varying in temperature between six thermal pools, it's anything but. The stark, linear architecture plays on light, form, texture and sound to create a natural, relaxing retreat. If the water isn't enough to soothe you, a range of pampering treatments should do the trick. If you're booking ahead, be aware that the hotel and spa close annually from mid-April to mid-June.
Hotel Therme Vals, Vals, Switzerland (00 41 81 926 8080; www.therme-vals.ch). Doubles start at €136 (£93) including breakfast and access to the thermal suite.
Sumiya Ryokan, Japan
Easily reached from Kyoto by the Sagano "romantic" train, Sumiya's claim to fame is that The Beatles once stayed here. Don't let that put you off, though. More than 100 years old, this is one of the most traditional of Japan's ryokans, with quintessential Japanese architecture, an imaginative menu and access to several picturesque outdoor bathing pools - both within the ryokan and a short walk away, hidden in scenic woodland. If you're shy, one of the bedrooms also has a private wooden bath.
Sumiya, Sanjo-sagaru, Fuyacho, Nakagyo-ku, Kyoto, Japan. Doubles start at £314, half-board, including language assistance, through Into Japan (01865 841443; www.intojapan.co.uk).
Hope Springs Resort, US
This 10-room former 1950s motel, a 20-minute hop from Palm Springs, has been given a long-overdue makeover by the new owners, a style-savvy graphic designer and record company founder from LA. The interiors are now a triumph of cosy minimalism, with Eames and Saarinen furniture, platform beds, exposed concrete floors and a groovy suspended fire-pit in the lobby. If you're more interested in the spa facilities, there are three spring-fed swimming pools in the courtyard. A long list of massage treatments is on offer, and yoga classes can be arranged.
Hope Springs Resort, 68075 Club Circle Drive, Desert Hot Springs, California, US (001 760 329 4003; www.hopespringsresort.com). Doubles start at $165 (£97), including breakfast.
Terme di Saturnia, Italy
The main attraction at this Tuscan resort is the spa with its thermal spring and four outdoor thermal pools. The resort - along with the local village - takes its name from Saturn who, according to Roman mythology, took a bolt of lightning and threw it down here, causing warm, sulphurous water to spill from a volcano.
Terme di Saturnia, Saturnia, near Grosseto, Italy (00 39 05 64 600 111; www.termedisaturnia.it). Doubles start at €370 (£264)Reuse content