Many data layers are available on the GIS server. The data is grouped in broad categories into a series of folders. The most commonly used folders are:

• AerialPhoto – black and white aerial photography from the entire state of Missouri, by county.
• BaseLayers – ArcGIS Layer files – predefined layers combined with symbology. There are subfolders within this folder for census, distbnd (districts and boundaries), facility, natural, trans
• Census2000 - census tracts, blocks, block groups and tabular data from the 2000 census.
• District_bounds – political boundaries, district boundaries, city limits, zip codes etc.
• Environ –environmental exposures, such as landfills, hazardous waste sites, pesticide dealers etc.
• Facility – hospitals, daycares, nursing homes, trauma centers, schools, etc
• Natural – basic geology, fault lines, rivers, streams, lakes, land use
• SurroundStates – some really basic information for the United States
• Trans – transportation: airports, railroads, highways, local streets

Files in ALL CAPS are old directories. DO NOT USE DATA IN THESE DIRECTORIES FOR NEW PROJECTS!!! These directories are kept ONLY for backward compatibility with older projects. These ALL CAPS file names will not be updated.