Direct Download of National Transportation Atlas Database (NTAD) Geospatial Files
The Highway Performance Monitoring System (HPMS)
The Highway Performance Monitoring System (HPMS) Layer is provided by the Federal Highway Administration (FHWA), and provides data that reflects the extent, use, condition, and performance of the public roads in the United States. It consists of the All Road Network of Linear Referenced Data (ARNOLD) and Section Data which is the attribution. ARNOLD and Sections are linked though linear referencing. This data is analytical for the purpose of supporting transportation program, funding and policy decisions at a national level. Operational applications such as navigation and routing may take advantage of HPMS with the understanding that it represents the average and not “real-time” of the system. The HPMS data privided through the link below is a zipped ESRI Geodatabase, containing one feature class for all of HPMS.
All Roads Network Of Linear Referenced Data (ARNOLD)
The All Roads Network Of Linear Referenced Data (ARNOLD) Layer is provided by the Federal Highway Administration (FHWA), and derives and is collected from State DOT road data. ARNOLD consists of locations of all roads in the U.S., and has limited attribute data. ARNOLD can be used by the public to create linear reference models. The ARNOLD data privided through the link below is a zipped ESRI Geodatabase, containing 51 feature classes, with each feature class being a state's ARNOLD submission to FHWA, including DC.
For additional geospatial information and datasets on NTAD, please see the NTAD Open Data Catalog.