Does anyone know where the classical music venues are in Prague? I have in mind orchestral/chamber music concerts which are informal, i.e. where you wouldn't feel out of place turning up in everyday casual clothes. I'd like to attend at least one classical performance when I next go to Prague, but am slightly intimidated by the thought that it might be very formal. I'd heard that Czechs like to "dress up" to go to the theatre/opera, and I was wondering if the same applied to classical concerts. At the Rudolfinum, for instance. "Posh" or not? If so, are there any other venues in Prague where they give informal classical concerts? Is there a website where you can find a programme for this kind of thing?