Copenhagen. Getty Images In the heart of Northern Europe, Copenhagen thrives, a city spun from the threads of ancient legends as enduring as its time-worn cobblestones.

And yet, Copenhagen's reputation as a must-visit city -- especially in the eco-friendly category -- has been on the rise for quite some time now. Over three million visitors flock there every year ...

But what makes Copenhagen Copenhagen is its unique college town energy, in which the city’s Harvards and Yales are the kitchens of Noma and Geranium, attracting talent from all over the world ...