Remisens Premium Hotel Ambasador (5*), Opatija

One of the finest spa hotels in Croatia, the Ambasador belies its 1960s exterior thanks to a complete overhaul in 2013. Two of its ten floors are given over to pools and saunas, where high-end treatments and massages are offered, along with prime panoramic views over the Kvarner Bay. The Villa property next door provides more privacy, but with access to the spa, terrace restaurant and bars in the main hotel.