Not a hall at all, but a monument on a hill. The Kaiser-Wilhelm-Denkmal stands on the Wittekindsberg above the Porta Westfalica, the gap where the Weser breaks northward through the hills onto the plain, and it takes the form of a great stone canopy sheltering a standing figure, with terraces cut into the slope beneath. It was built in the 1890s to designs by Bruno Schmitz, who specialised in monuments of exactly this scale and rhetoric. Summer performances are given on the terraces, the audience seated on the hillside with the river below, and opera in concert has been among them — Verdi more than once.