Athens, Greece
Best for: ancient wonders
Obsessed with ancient Greece? Athens' Acropolis was built in the fifth century BC, so it's no surprise that architectural enthusiasts descend upon one of the world's oldest cities year-round to admire one of the best surviving examples of ancient architecture. The Parthenon, dominating the hill of the Acropolis, is a logical place to begin your pilgrimage. While you're in the area, pay a visit to the Acropolis Museum.
The city itself is, in effect, a living case study of myriad architectural schools and styles. Greco-Roman? Check. Neoclassical? Check. Modern? Check. If you're more intrigued by contemporary design, set aside a morning to visit the Stavros Niarchos Foundation Cultural Centre (SNFCC), an impressive structure highlighting Athens' new groove through art, music and sport, with not a Doric column in sight.