Copenhagen

Copenhagen needs 3 days: Nyhavn and the center on one, the alternative Christiania neighborhood and Vesterbro on another, and Tivoli Gardens on the third. May-September brings the best weather. It's expensive, among Europe's priciest capitals. It's consistently ranked among the world's happiest and most livable cities, with more bicycles than residents and a cycling culture that made it a global model for sustainable urban mobility.