If the Acropolis is the city's historic centre and Syntagma its political one, Omonia is its practical centre, a transit hub and the location of key administrative offices. It's not a destination, but you'll inevitably pass through here – perhaps on your way to neighbouring Exarhia and the National Archaeological Museum. Exarhia is most famous for its squat scene and its vocal anarchists, but it's an interesting mix of students (it’s near the universities), artists, actors, immigrants, families, old lefties and intellectuals, against a backdrop of graffiti and occasional riot police.