National Highway 179A, commonly referred to as NH 179A, is a national highway in India, which comes under Ministry of Road Transport & Highways, Government of India. It is a secondary route of National Highway 79. NH-179A traverses the state of Tamil Nadu in India.
Salem, Harur, Uthangarai, Thirupathur, Vaniyambadi.
Four laning of national highway 179A has been taken up along stretch from Harur to Vaniyambadi. Salem to Harur stretch is part of Chennai - Salem greenfield highway project which is also part of Bharatmala Pariyojana scheme. Chennai-Salem Greenfield Corridor under the Bharatmala Pariyojana, a centrally-sponsored and funded road and highways project, is a 277.30 km highway that involves the development of the Tambaram to Harur Section of NH-179B, Harur to Salem Section of NH-179A, Chengalpattu to Kancheepuram Section of NH-132B, Semmampadi to Chetpet Section of NH-179D and Polur to Tiruvannamalai Section of NH-38.