Hot destinations: touring two of Switzerland's top spa hotels

Switzerland is most vividly about enjoying the outdoors: skiing or hiking in the Alps, boat rides on lakes and rivers, or walking and shopping your way through historic towns and cities. Cafes, restaurants and museums can fill rainy or snowy days, but for a culture built on sport and fitness, the indoor complement to the athletic outdoors is the spa.

In the resort town of Lenk, in the Bernese Oberland (Bernese Highlands) - the higher part of the capital Bern - is the Lenkerhof Gourmet Resort. The Lenkerhof has been serving guests who have come to Lenk to "take the waters". You also have a choice of an indoor or outdoor pool (even when the snow falls). On the floor below is the fitness centre.

In the hotel's nacktbereich (saunas), there are seven rooms set at temperatures ranging from minus 1 degree Celsius, in the ice grotto, to 85 degrees Celsius in the Finnish sauna. In other words, you can literally stand naked in a freezer or cook in a wooden skillet, or go back and forth as you please. I was sweating it out in the Finnish sauna when, at precisely 5am, Sara came in, announcing in Swiss German what sounded like an "oof goose" (High German: , meaning "infusion"). Sara poured ice onto the hot stones of the sauna, and then flailed a towel with a whip-like snap in front of each occupant. The effect was to increase the heat momentarily to about the temperature needed to melt anodised aluminium. A couple of guys could not take the heat and left, with their heads down; the rest of the men stayed in, if only to not be outshone by the only woman present, who was enjoying herself as calmly as if she were sitting beside a fan on a veranda.

The Lenkerhof was built over a sulphur spring because sulphur water is believed to alleviate the symptoms of everything from rheumatism to digestive problems - at least it was until Swiss insurers stopped paying for policyholders to take the cure. That caused an immediate cash-flow crisis among hoteliers and clinicians engaged in the ancient trade of offering water that smells like rotten eggs to anyone willing to drink and bathe in it.

One room in the Lenkerhof's spa is a sulphur grotto, where you can inhale sulphur and drink sulphur water. On your way there, sulphur water sprays you from the ceiling.