Wilhelmina was responsible for the building of the Margraves' Opera House in 1748. The austere façade is hemmed in by 18C burghers' houses. The interior, with the stage and apron, forms an area of astonishing depth. The stalls used not to have any seats, being set aside for dancing. The period decoration by Giuseppe Galli Bibiena from Bologna is of an exuberant richness.