All it takes is one up-and-coming neighborhood to make a city feel reborn, but in booming, forward-thinking Oslo, two areas are alive with everything new in art, food, and design. The first is Thief Island, or Tjuvholmen, a former prison islet that's now filled with glittering glass art galleries and restaurants—and the crown jewel, the Renzo Piano–designed Astrup Fearnley Museum of Modern Art, a beautifully mod vessel for works by contemporary all-stars including Jeff Koons and Olafur Eliasson (47-2293-6060). The Astrup has loaned some Richard Princes and Andy Warhols to The Thief, the sleek, granite-and-glass hotel next door that's cozy inside thanks to its big fireplace and Marimekko-esque upholstery designed by young Norwegians (47-2400-4000; doubles from $358).

A 20-minute walk from Thief Island is the Vulkan neighborhood, whose industrial edge has made it the center of the city’s young creative scene. At its heart is Mathallen Oslo—a new food hall with stalls selling pies and fabulously fibrous Scandinavian bread (Maridalsveien 17)—but the area’s flash factor started with the opening of Bar Vulkan, an indoor-outdoor restaurant/club where the stylish eat burgers and drink rosé (Maridalsveien 17; 47-9400-8182; entrées from $31). Today, Vulkan is so loaded with snob-approved coffee shops and cutesy clothing stores that on weekends it's swarming with locals—they're all looking for a hit of the city’s new brand of cool.