Stockholm

Stockholm is spread across 14 islands connected by bridges, and ships approach through a long archipelago of rocky islets and summer houses. Most cruise ships dock at Frihamnen, about three kilometres from the old town. Gamla Stan, the medieval island at the city's centre, has narrow cobblestone lanes, the Royal Palace, and Stortorget, a small square with coloured merchant houses from the 1600s. The changing of the guard at the palace happens daily around midday. The Vasa Museum on the island of Djurgården is the single must-see, housing a nearly intact 17th-century warship that sank on its maiden voyage and was raised 333 years later. The ABBA Museum is next door if that's your thing. Skansen, the world's oldest open-air museum, is a short walk further and has historical buildings and Scandinavian wildlife. Östermalmshallen, a covered food market, sells gravlax, meatballs, and herring in forms you didn't know existed. Fika, the Swedish coffee-and-pastry ritual, is practiced everywhere and taken seriously.