A Festspielhaus or Festival Theatre is a German language term describing a theatre designed for opera or music festivals.
There are several examples of Festival Theatres in the German-speaking world: Bayreuth Festspielhaus or the Bayreuth Festival Theatre in Bayreuth, Germany Festspielhaus Baden-Baden in Baden-Baden, Germany Grosses Festspielhaus (Grand Festival Hall) in Salzburg, Austria Kleines Festspielhaus (Little Festival Hall) in Salzburg, Austria Festspielhaus St. Pölten in St. Pölten, Austria Festspielhaus Hellerau in the district of Hellerau, now part of Dresden, Germany; see info in the German Wikipedia FestSpielHaus, in Munich, Germany