DeLorme Professional Weblog

If you have visited the XMap Web site, you should have seen a selection of screenshots that were created for the purpose of illustrating a diverse variety of applications for the software. While these screenshots include examples of some of the datasets that DeLorme offers for use with XMap, the majority focus on data that was either developed using XMap’s data creation tools or that was integrated from third-party data sources. A commonly asked question is, “From where does this third-party data originate?”

There are countless sources of spatial data in both vector and raster format, much of which can be freely downloaded from local, state, regional, or national government Web sites or sometimes from educational institutions. Try typing “GIS Data” followed by a geographic area of interest into a Web search tool and you will often uncover libraries of data that will meet your needs.

For instance, here in Maine, the state-level GeoLibrary Board maintains and distributes almost 150 different data layers in vector format — everything from hospital locations to eagle nesting sites. Depending on the type of data, shapefiles can be downloaded for selected municipal areas, by USGS quad, or for the entire state. The site also offers recent high-resolution orthoimagery in MrSID format that can be used as a base map for your XMap projects.

Virtually all 50 states as well as the District of Columbia (which has one of the more extensive lists of data layers) have a GIS data repository where you can browse and download data layers. To help in your search, DeLorme is in the process of developing a data resources page that will provide a thorough list of agencies and organizations that offer spatial data. To begin with, we have pulled together a list of state-level data libraries to which we will eventually add other GIS data sources.

If you know of a data resource page that should be added to the list, please e-mail the details to prosales@delorme.com