Hotel Ambasador

Hotel Ambasador sits above Opatija's Lungomare promenade, and its spa centre is built around a sauna circuit rather than a single steam room: a Finnish sauna, a softer low-heat Finnish sauna, a Turkish bath, a vertical kneipp walk and an ice fountain, plus a relax zone with heated deckchairs and a seven-person whirlpool. Minimum age for the sauna area is 16, and the clothing-optional policy applies there.

Beyond the sauna centre there's a fitness room fitted with Matrix equipment, a RAXUL multifunctional spa room, separate beauty and massage rooms, and a Private Spa for two for couples wanting their own space. The signature treatment listed is a lymphatic drainage massage, priced around $59, described as a way to reset after travel or a day on the coast.

Water options stretch beyond the sauna zone: an indoor pool filled with heated seawater, an outdoor seawater pool, and an indoor whirlpool. Staff communicate in English, and valet parking is included for arriving guests.

This is a hotel spa in the strict sense — there's no day-pass option and no walk-in access, so a stay at Hotel Ambasador is the way in. Treatments can be booked for couples, and the facility is pitched at travelers already staying in the hotel's rooms or suites rather than locals looking for a one-off visit. Given the setup — multiple sauna types, two seawater pools, and private treatment space — it functions more as an amenity woven into a longer stay than a stand-alone spa destination.