Data Services Division - Highway Use And Characteristics

The Maryland Department of Transportation State Highway Administration (MDOT SHA) Data Services Division (DSD) is responsible for

  • maintaining a current data inventory of the highway system
  • drafting and dissemination of maps
  • collection, analysis, reporting and distribution of Traffic Monitoring System (TMS) data

DSD serves the entire agency and provides highway information, mapping information, and TMS data to the State of Maryland, local governments, the public and the federal government. The Federal Highway Administration uses highway information from the road inventory database to apportion federal funding to the State of Maryland.

Traffic Monitoring System

A summary of the traffic volume data collected throughout Maryland.

Mileage Inside the Municipalities Reports

Mileage information inside a municipality.

Highway Location Reference

Provides a method for uniquely identifying roadway locations (mile points) and to identify data elements that are most commonly requested.

Highway Maps

A large selection of interactive Geospatial Information Systems (GIS) maps and data sets available from MDOT SHA.

County Maps

Maryland's Interstate and Beltway Mileage (PDF, 43kb)

Summarizes the mileage of the Baltimore Beltway, Capital Beltway and The Interstate system.

Annual Reports

Traffic Volume Maps

Annual Average Daily Traffic (AADT) on state roads.

Annual Highway Mileage Reports

Yearly mileage Reports for State, State toll, county, and municipal roadway systems. Key terms can be found here.

Annual Vehicle Miles of Travel (PDF, 526kb)

Travel estimates for each county by Functional Class.

Highway System Mileage by Year (PDF, 1.76mb)

Mileage by county on the SHA, Toll, County, and Municipal roadway systems for the years 1980 to the present.


The information in these documents are provided as a public service by the Maryland Department of Transportation State Highway Administration (MDOT SHA). MDOT SHA makes no claims, promises or guarantees about the accuracy, completeness, or adequacy of the contents of these documents and expressly disclaims liability for any errors and omissions in the contents of these documents. All route, traffic, and travel data being made available by MDOT SHA are developed to support internal uses, primarily transportation planning. Any and all data are provided "as is," with the understanding that no warranty of any kind, implied, expressed or statutory, is given with respect to the contents of these documents. Any and all conclusions or products derived from the data are the sole responsibility of the user. Information presented on this website is considered public information and may be distributed or copied.