Boy that's confusing, we've only got restrictions by age, usually 14 and 18 (and X for porn), that's it! No indication on the content of the film (at least at the cinema, on DVD covers they might me more specific).
In Italy we can watch Eyes Wide Shut since 14 years old while in the UK they have to wait till they're 18.
THX is set to 14 in Italy and 15 in the UK. Instead, Finnish kids can watch LUH's "nudities" since 11 years old.