Why Go Now: World-renowned architects are adding 21st-century design to the medieval landscape of Portugal's second-largest city—the Casa da Música theater by Rem Koolhaas and the Serralves Contemporary Art Museum by Pritzker Prize–winning Portuguese architect Álvaro Siza.
The Details: If you want to stay in the old part of town, the Pestana Porto (doubles from $226) is a boutique property with balconies overlooking the Douro River. Or check in to the intimate Guest House Douro (doubles from $185), where eight light-filled rooms have large French windows and marble baths. The best restaurants and bars are concentrated in the tony Foz district. At the beachside ShiS (dinner for two $100), you'll find Asian-inflected Portuguese dishes such as crab risotto with avocado ice cream. A stone's throw away is Praia Da Luz (dinner for two $65), a casual steak house where the water laps right up to your table. In the heart of Porto, stop by the 88-year-old Café Majestic for traditional rabanadas (mini French toast).
T+L Tip: Don't miss Livraria Lello, a neo-Gothic bookstore with soaring interiors and a stained-glass skylight.