Romanian Athenaeum, Bucharest

Undoubtedly one of the most iconic buildings in the city, the Romanian Athenaeum is used by the world-renowned George Enescu Philharmonic Orchestra, who perform classical concerts and one-off events from September to May. You can only see  the grand  interior if you go to one of their concerts, though you can try to take a peek at it through a window. Most spectacular are the curved inner walls which are decorated with images of important moments in Romanian history.