The smallest of GLMZ's Lost Blocks, the Caulfield Pocket consists of only three buildings arranged around a central courtyard, occupying less than half a city block in the Circuit District. It is named for Caulfield Lane, the street that once provided access — a narrow pedestrian passage between two commercial buildings that opened onto the courtyard. The passage is now a wall. The courtyard is visible from the rooftop of the adjacent Halsted Parking Structure, which rises three stories above the pocket's buildings, providing a direct overhead view that supplements satellite imagery.

One researcher, Dr. Yuki Anand-Petrov, lowered a camera on a rope from the parking structure roof during her cartographic survey. The camera descended approximately eight meters before the rope went slack — not cut, not tangled, slack, as if the distance between the roof and the courtyard had shortened while the camera was in transit. The footage recovered shows an empty, clean courtyard with decorative paving stones arranged in a geometric pattern. At the center of the courtyard is a fountain — a simple basin-and-column design, perhaps two meters tall. The fountain is running. Clean water flows from the column into the basin and recirculates. The courtyard is maintained. The paving stones are swept. The fountain works. Nobody maintains it. Nobody sweeps it. Nobody repairs the pump.

Thermal imaging shows approximately 15 heat signatures within the three buildings. The Caulfield Pocket shows the least activity of any Lost Block — the signatures move infrequently, spending long periods stationary in what appear to be seated or reclined positions. The Shadow Census's power consumption analysis shows minimal electrical usage, well below what would be expected for 15 occupants. Either the residents use very little power, or the residents are not doing the things that require power. The Caulfield Pocket is the only Lost Block that has shown no measurable growth over the ten-year observation period. It is stable. It is small. It is the only Lost Block where you can stand on a rooftop and look directly down into the space you cannot enter, watching a fountain run in a courtyard you'll never reach.