This project was completed for the Maryland Department of Planning in the Winter of 2008-2009. Road density in this analysis was defined as square meter of road way per square meter of available land. This method accounts for the difference in road dimensions between interstates, highways and county roads. Two road data sets were combined to determine the proper road width. The Highway Performance Monitoring System (HPMS) road data set contains information about road widths, but only for major highways and interstates. The MD SHA centerline dataset contains every road in the State of Maryland, but does not contain road widths. To fix this issue, county roads in the MD SHA centerline dataset were affixed a road width of 30 feet and merged with the HPMS road data set. This accounted for the difference in road dimensions of the highways and interstates while still preserving the detail of the SHA centerline data set. Finally, a grid was generated and unioned with the road width data set. At this point the percentage of road per grid cell was calculated for each county. Each county grid was then merged to give the map displayed to the right.