20 · P. O. STORAGE
Research representation: boundary trace. Architectural checks: pending.
Basement
Historical room number: 20
Source relationships · not a verified physical connection
- has opening (observed, unreviewed): Door candidate 20-corridor-north
- has opening (observed, unreviewed): Door candidate 20-corridor-south
11 recorded properties
Still to extract or check- Clear dimensions and wall thicknesses
- Regional floor/ceiling elevations
- Complete opening schedule and construction details