GIS & Mapping Basics - FAQs
Frequently Asked Questions
If the following questions and/or the other sections of the GIS & Mapping website don't answer your question(s), please see the Contact page to ask a staff member.
GIS stands for Geographic Information System. A GIS is a computer system - Hardware and Software - that helps analysts discover relationships between and among sets of computer-readable, geographically referenced data. These relationships are not easily seen or understood without the aid of this technology. For more details, you can read a longer explanation at GIS.com (external website).
GIS enables the County to display and analyze geographically referenced information. More than 75% of County information can be referenced geographically (e.g. street addresses, parcels). Dozens of agencies rely on this information to support their operations, create efficiencies, and allow for sophisticated analyses. Public Safety agencies can pinpoint locations of events like fires and crimes. The Department of Systems Management for Human Services uses GIS to provide housing and population forecasts used for planning by several County agencies. GIS data that the County uses for making decisions is updated, maintained, and made available as business requires, often on a daily basis.
By making the County's maps and data accessible quickly on-line, residents and businesses have access to a wealth of information to help to better understand the County that they live and conduct business in. GIS allows decision makers and residents to visualize complex information. It helps build understanding and consensus between government and residents on issues that confront the community. GIS also makes the County Government more efficient. Improved efficiency means better services at less cost.
Yes. As of July 1, 2009, GIS & Mapping Services has taken over responsibilities for map sales from the recently closed Maps & Publications Center. A series of large printed wall maps is available for purchase in the GIS & Mapping Services office. These maps include products created by GIS & Mapping Services in addition to those compiled by other County agencies. For a list of wall maps in the series, click on the Paper Maps page from the Off-line Products and Services section. Some wall maps are available to view and download for free in the Wall Map section of the online Map Gallery.
Yes. Fairfax County coordinates the publication of a street atlas book on a yearly basis. In addition to streets and landmarks, the County supervisor district boundaries and the tax map grid have been overlaid on the map. A companion street atlas index providing address ranges and tax map numbers is available for download. See price list for details.
Yes. Our collection dates back to 1937. For more information, click on Aerial Imagery in the Off-line Products and Services section. Digital aerial imagery is also provided in several GIS applications found in the On-line Products and Services section.
No. House location plats are maintained by the Zoning Administration, located in the Herrity Building. Photocopies are available. For more information, call 703-222-1082.
Yes. As of July 1,2009, GIS & Mapping Services has taken over responsibilities for map sales from the previous Maps & Publications Center. Whole County map books (property, zoning, soils, etc.) as well as individual map book pages ( zoning map book only) may be purchased from the GIS & Mapping Services office. See price list for details.
Please note that weekly-updated map book pages, in addition to a library of historic map book pages, are available to view and download for free in our Digital Map Viewer application found in the Online Products and Services section.
No. As of April 1, 2010, Subdivision Plats and Deeds recorded in Fairfax County are only available through the Court Public Access System (CPAN). Submitted development documents (site plans, grading plans, etc.) are available through the Department of Public Works & Environmental Services Plan & Document Control section at 12055 Government Center Parkway, Suite 506.
Yes. For more information, click on Maps - Contour Maps from
Maps page. Updated contour maps are available to view and
download through our Digital Map Viewer in the On-line Products and Services