》They are constructed and maintained by the central government.
》According to NHAI the National Highways constitute only 1.7% of the road network, but carry about 40% of the total Road traffic of India.
》The development and maintenance of National Highways system is carried out through three agencies--
1. National Highway Authority of India (NHAI).
2. State Public Works Departments (PWDs).
3. Border Roads Organisation (BRO).
》In order to boost to the economic Development of the country, the government has embarked upon a massive National Highways Development project (NHDP) in the country.
》The NHDP is the largest highway project ever under taken in the country.
》The NHDP is being implemented mainly by National Highways Authority of India.
