Otium Spa Gjøvik: Complete Guide to the Sauna and Polar Bear Plunge on Lake Mjøsa

On the western shore of Norway’s largest lake, inside a hotel that also houses a rooftop restaurant, a steakhouse and a cinema, Otium Spa runs on a simple pitch: get properly hot in a Finnish sauna, then jump into water cold enough to have earned the nickname “polar bear plunge.”

Gjøvik and Lake Mjøsa

Otium Spa occupies a prime position on the shore of Lake Mjøsa — and Mjøsa is no ordinary lake. At 365 square kilometres, it’s the largest lake in Norway, and its presence shapes both the landscape and the atmosphere of the entire Gjøvik district. The spa takes full advantage of the setting, with its sauna and pool areas oriented toward the water.

Gjøvik itself is a university city and regional centre on Mjøsa’s western shore, roughly 100 kilometres north of Oslo — close enough for a comfortable day trip from the capital, but far enough to feel like a proper escape from the city.

Otium Spa vs. KOK Mjøsa in Hamar

Otium isn’t the only sauna on Mjøsa’s shores. Directly across the water, in Hamar, KOK Mjøsa runs a floating sauna out on the lake itself — a different format built around a similar setting, and worth knowing about if you’re weighing up where to spend a Mjøsa sauna day.

	Otium Spa (Gjøvik)	KOK Mjøsa (Hamar)
Format	Indoor hotel spa with pool, sauna, steam room and cold plunge	Floating outdoor sauna directly on the lake
Best for	A full spa day — heat, cold, treatments and dining under one roof	A focused, classic Nordic floating-sauna session
Access	Hotel guests and day visitors, ticketed entry	Bookable sauna sessions on the water
Setting	Purpose-built spa facility beside the lake	Sitting directly on Mjøsa’s surface

Neither is better than the other — they’re simply different ways of using the same lake. Otium suits a slower, more complete wellness afternoon; KOK Mjøsa suits visitors chasing a more elemental floating-sauna experience. Travellers touring inland Norway sometimes do both, one on each shore.

Finnish Sauna, Steam Room, and the Polar Bear Plunge

Otium Spa is built around two complementary heat experiences: a Finnish sauna running at classic high, dry heat, and a steam sauna offering high humidity at a gentler temperature. The Finnish sauna delivers the penetrating dry heat that defines Scandinavian sauna culture — the kind that invites a long, unhurried sweat. The steam room is softer, better suited to easing into the heat or giving your lungs a break between rounds.

Then comes the payoff: the cold plunge pool, informally known at Otium as the “polar bear” plunge. Following sauna or steam heat with a deliberately cold immersion is the whole point of contrast bathing, and the physiological case for it is well established — reduced muscle soreness, improved circulation, and a genuine, noticeable lift in mood and alertness. Doing it here comes with a bonus: the plunge pool looks straight out over Mjøsa, a view that turns particularly dramatic in winter, when mist rises off the water and the surrounding hills carry snow.

Facilities and Treatments

Beyond the sauna, steam room and cold plunge, Otium Spa runs a heated pool, a jacuzzi, a foot spa and a gym, plus a treatments menu that includes facials and massage. The treatments are designed to extend the sauna circuit rather than replace it — bookable on top of general spa access for visitors who want a longer, more indulgent stop than a quick sauna-and-plunge session. The spa sits inside Quality Hotel Strand, which also houses a rooftop restaurant, a steakhouse, a cinema and a cultural centre under the same roof — so a spa session pairs easily with dinner without anyone needing to leave the building. Strawberry Hotels maintains consistent quality standards across its Norwegian portfolio, and Otium Spa reflects that commitment.

Best Time to Visit

Otium Spa runs year-round, and the lakeside setting works in every season — but winter is arguably when it’s most striking. Moving between a heated pool and a cold plunge while Mjøsa lies frozen or half-frozen just outside creates a contrast that’s genuinely hard to replicate in summer. That said, a bright Norwegian summer evening on the same shoreline has its own appeal, and the spa’s opening hours don’t change with the seasons — there’s no wrong time to visit, only a different mood depending on when you go.

Practical Info: Hours, Access, and Price

Otium Spa keeps fairly tight hours: Monday to Thursday 15:00–20:00, Friday and Saturday 13:00–20:00, and Sunday 11:00–17:00 — worth building into your schedule before you arrive, since the spa isn’t open around the clock like some hotel wellness areas. Access doesn’t require a hotel booking: day visitors are welcome with an entrance ticket, and children, youth and students get discounted rates. Pricing sits in the mid range for a Norwegian hotel spa. As at nearly all Norwegian hotel spas, sessions are mixed-gender throughout and swimwear is required. For those wanting the fuller experience, Strawberry Hotels also offers a wellness package pairing an overnight stay and a two- or three-course dinner with full-day spa access. The address is Strandgata 15, 2815 Gjøvik; check Otium Spa’s own booking page for current prices and availability.

Getting There

Gjøvik sits on Mjøsa’s western shore, about 100 kilometres north of Oslo by road — an easy day trip or a natural overnight stop if you’re travelling further into inland Norway. Gjøvik itself is a compact university town with its own lakefront promenade, worth a short walk before or after a spa session; the same shoreline that gives Otium Spa its view continues along much of the town centre. Combined with Hamar and Lillehammer further up the lake, Gjøvik forms part of a loose loop for travellers who want to circle Norway’s largest lake by road, taking in more than one lakeside town on the same trip. For a single-destination visit, though, Otium Spa works perfectly well as a there-and-back day trip from Oslo, with the spa itself as the main event rather than one stop among many. If you want to turn the trip into a broader Mjøsa sauna tour, Hamar sits across the lake on the eastern shore, with its own cluster of floating and lakeside sauna experiences.

Continue Exploring

For more sauna options around Norway’s largest lake, see our guide to things to do in Hamar, which covers the floating saunas and other attractions on Mjøsa’s eastern shore. For the full profile of this spa — including exact coordinates and the amenities list — see the Otium Spa Gjøvik listing.