Building 9000, located on the border between the Shelf District and the Circuit, has been under continuous private modification since 2170 — thirty years of renovation by a succession of owners who each, independently and without knowledge of their predecessors' intent, expanded the structure's interior. The building's footprint has not changed. Its exterior dimensions have not changed. Its interior volume has increased by a factor that our surveying equipment cannot agree on, because the measurements change depending on the path taken through the building.

The current owner, who purchased the property in 2198, discovered that the building contains rooms that cannot be reached from other rooms by any continuous path, stairways that connect floors that should not be adjacent, and corridors that are longer on the return trip than on the outward journey. An architectural survey commissioned by the owner measured the interior at 4,200 square meters. The building's footprint is 800 square meters across three floors — a maximum possible interior of 2,400 square meters. The surplus 1,800 square meters exist. They are real rooms with real walls and real floors. They are simply more space than the building has room to contain.

The modifications, taken individually, are mundane. A wall knocked down here, a room added there, a corridor extended. None of them violate building code in isolation. But cumulatively, they have produced geometry that does not close — spatial relationships that are locally Euclidean but globally impossible. You can walk in a straight line through the building and arrive at a point that is not on the straight-line path. You can descend a stairway and arrive on a floor above where you started. The building is not haunted. It is simply wrong, in a mathematical sense that our surveyors find more disturbing than any ghost.

We have ordered the building vacated pending structural assessment. The owner has complied. He reports that the building resists being empty — doors that were closed are found open, lights that were off turn on, and on two occasions, furniture that was removed was found returned to its prior location by the following morning. The building wants to be used. We do not know by whom.