Built between 1744 and 1748 for the Margravine Wilhelmine of Brandenburg-Bayreuth, this is one of the finest surviving Baroque court theatres in Europe and a UNESCO World Heritage Site. The auditorium is a marvel of painted wood, gilded stucco, and tiered boxes — all intended to project the power of a minor German principality. Wagner was drawn to Bayreuth partly because of it, though he ultimately found the stage too small for his ambitions and built his own theatre instead.
The opera house was built by court architect Giuseppe Galli Bibiena, and the entire interior is executed in wood painted to simulate marble — a common Baroque technique that achieves a remarkable visual richness at a fraction of the cost of actual stone. The building hosts a concert season outside the Wagner festival period; if you can attend a performance here, do. It's the right way to experience a theatre that was built to be used, not merely admired.