An open-air stage in the grounds of the old monastery at Gräfinthal, in the Bliesgau country south-east of Saarbrücken, the Naturbühne works only in the warm months and only for as long as the light lasts. Audiences sit under the sky; the medieval walls do the work that scenery would otherwise have to do. Verdi's Aida has been among the operas mounted there, on a scale the setting rather than the budget dictates.