List of major district roads in Tamil Nadu

In Tamil Nadu, there is a separate Highways Department (HD) which was established in April 1946 and renamed as Highways & Minor Ports Department (HMPD) on 30 October 2008. HMPD of Tamil Nadu is primarily responsible for construction and maintenance of roads including national highways, state highways and major district roads in Tamil Nadu.

Roads with traffic density less than 10,000 PCUs but more than 5,000 PCUs are designated as major district roads (MDR). MDRs provide linkage between production and marketing centres within a district. They also provide connections between district and taluk headquarters with the state highways and national highways. Construction and maintenance is carryout by the Highways Department for MDR along with state highways and ODR. These roads have a minimum width of 15 meters.

Lane wise distribution
Details of lane wise distribution of MDR roads in Tamil Nadu as of March 2013:

List of MDRs
List of Major district roads in Tamil Nadu (as of March 2019).