The Upper House sits in the middle of the plateau of Leng. From the outside it appears as a low flat stone building with sloping walls and a single large entrance. It is surrounded by a circle of widely-spaced, featureless obelisks. The House is a midpoint between Aldebaran and Earth, and is the closest to our world that The King in Yellow can come without aid.
On the inside, however, the House is a vast, impossible labyrinth of corridors and chambers that constantly circles back on itself in ways that defy geometry. Stairs that have been climbed for many minutes end up in the same chamber they started in, rooms appear different when reached a second time, corridors twist and widen and narrow unpredictably. Many of the walls are painted with scenes of alien cities, races and wars.
The investigators came to the Upper House with Malcolm Quarrie and it was here that Umberto chose to murder him to prevent him from bringing the King to Earth. After wandering the halls of the Upper House for at least 2 days, the investigators followed the sound of pipes to a high open plaza where The King in Yellow stepped down from Aldebaran through a magical gate between 2 great pillars.