The Chamber of Spheres
The Chamber of Spheres was discovered by the People of Pegre, the sewer-folk living in Petit Charouse, a few years back, but it was only when Madelene Prevoye's entranced wanderings took her there that the party discovered it. The Chamber was a round, domed room, a good 20 meters across and half as high, made of milky white marble, smooth and unblemished. In the center, a pedestal of the same substance rose up from the floor, surmounted on the top by a large, translucent red stone.
More notably, a large gemstone-encrusted door was inset into one wall, from which The Caged Beast was released. The Chamber collapsed shortly after the slaying of the Beast. A recent discovery in the root cellar of the Dutchess de Bourjonais has shown that the ruins were near the surface of the city, and can be accessed through the cellar. The Invisible College is beginning excavation, quietly.