A sheet of water pours off a curved wall inside the swimming pool changing room. I'm standing in front of it in bathrobe and flip-flops, a bit unsure what to do next. I have been told to report here at 4.20pm. The clock on the wall says that is the time. And I'm in Switzerland, so I know it must be right.

All of a sudden, the walls of water part, and I'm ushered into the inner sanctum of the Bogn Engiadina, an impressive "Roman-Irish" baths complex high in the mountains, at 1,250m, in the ski resort of Scuol.

While the Romans swore by the relaxing properties of steam baths at various temperatures, the ancient Irish enjoyed bathing in hot, dry air. When bathing became popular again in the 19th century, these two styles were combined in resorts in Germany and Switzerland. The spring water that bubbles up from the ground here has been drawing visitors since the 1800s. Skiers are latecomers, discovering the area in the 1940s and 1950s.

There are 25 springs in Scuol – producing different mineral waters. Waters from the Lucius and Bonifacius springs are administered only under supervision in the trinkhalle (drinking hall) because of their laxative powers.

Bogn Engiadina, which celebrates its 20th anniversary next year, is a huge spa with six indoor and outdoor pools, steam room, solarium, sauna and fitness centre, drawing visitors in winter and summer. It's particularly attractive in winter, perfect for resting tired legs after a day on the slopes. The bathing and sauna areas are open until almost 10pm most nights, so there's time to fit in a trip after the lifts close.

Too often, the end of the day on a ski holiday means heading to the bar. Bathing in mineral pools and relaxing in a sauna instead means your body will thank you rather than curse you on the slopes the next day.

And the great thing about Scuol is that you're not made to feel a wierdo for doing this. Many hotels offer wellness breaks. Mine, Hotel Belvédère, provides free ski passes and a pass for Bogn Engiadina, to which it is linked via a tunnel. Padding through it in robe and slippers, staring out at the snow-covered trees in the dark is surreal and magical. There, for two and a half hours, I must wear nothing but flip-flops, and carry only a toga and an instruction card. The point of the treatment is to gradually heat your body up, then cool it down, through timed sessions in saunas, steam rooms and pools. I move through a 54C "warm-air room", a 70C "hot-air room", and steam rooms at 42C and 48C (where I bail out long before the allotted 10 minutes is up). Then I enjoy a honey massage looking out at the mountains, and dips in a whirlpool and a mineral pool. After braving the final cold-water pool, I'm wrapped up on a bed in a big red blanket, and reminded that this particular ski holiday isn't just about haring around the mountain.

That's what they think. Next day I take the first lift up from Scuol. Around the Jonvrai area there's a surprising amount to ski, and the pistes are very, very quiet (in January). Scuol is only 45 minutes by train from Klosters, but is almost undiscovered by the British market. The Motta Naluns ski area has 80km of pistes, from 1,250m to 2,783m. The villages of Scuol, Ftan, and Sent are all linked.

It's a great area for intermediate skiers, but it's also great for those who just enjoy winter walking. I see lots of walkers, strolling along in the sunshine at 2,000m-plus – not something I've seen in any other ski resort. Walking routes marked are in purple on the piste map, along with the red, blue and black runs. Cross country skiers will be happy here too: there's a 28km loop between Scuol and Martina, and many more trails in the Lower Engadine area.

I ski down to Ftan, noticing that the T-bar back up could do with an upgrade, and finally ski a 12km "dream run" to the village of Sent. The setting sun casts shadows over parts of the piste, and it's so quiet that, like on a country walk, when I see another person, we say hello.

I ski to a stop just above the Sömi bar, and briefly ponder an après-ski beer – the setting is so perfect. But I must press on, I'm not finished for the day. I've a spa to get to ...

• The trip was provided by Switzerland Tourism. SWISS (swiss.com) flies to Zürich from London City, Heathrow, Birmingham and Manchester from £120 return. More information from myswitzerland.com. Doubles at Hotel Belvédère (belvedere-scuol.ch) from 150CHF (around £100). Entry to Bogn Engiadina (en.graubuenden.ch) from around £17