The Geo-Database is the place where the most time is spent building the noise model. With the DXF and ASCII interfaces, a lot of common data from external sources can be imported and included in a comprehensive noise model. It is also possible to load a geo-referenced bitmap into the background and digitize on this canvas. DXF, ASCII interface and the background bitmap are all part of the Geo-Database. The data created in the Geo-Database are stored in an unlimited number of Geo-Files. To keep order in the multitude of Geo-Files, a sub-structure called “Situations” organizes the files in folders in a manner similar to how files are stored in folders in the Windows Explorer. An extensive collection of Geo-tools, view operations, and the selection and manipulation tools make the Geo-Database a highly sophisticated GIS type data entry and manipulation instrument. The Geo-Database hosts the SoundPLAN Manager (the project administration tool), the Library (the general storage area of data to be used in multiple projects), the Documentation (the producer of printed documentation on the findings of a single calculation run), the Spreadsheet (for comparing multiple calculation runs) and the non-modular graphics (for making overview graphics for presentations).