Design geeks must take the train from Copenhagen's city center to Orestad. The neighborhood is like a futuristic city with its innovative architecture, much of which looks like it's straight out of the Jetsons. Bjarke Ingels is arguably one of the world's most influential young architects and urban developers. His No. 8 building (above) was voted Best Residential Building 2011 at the World Architecture Festival and is a glimpse at the future of sustainable city living. Walk the grounds and be sure to check out the green roof.