Old numbering of road in India
National Highway 66 (NH 66) is a National Highway in India. This is the main National Highway to connect Pondicherry with Krishnagiri. It starts from Indira Gandhi Square in Pondicherry and runs north west till Tindivanam in Villupuram district then runs westward till Uthangarai via Thiruvannamalai and then joins NH 46 at Krishnagiri. NH 46 starts from NH 7 which is at from the junction of NH 66. The total length runs to .
The distance between Pondicherry and Tindivanam is widened into four lanes by Maytas - NCC Consortium.
Route.
Pondicherry - Thiruchitrambalam - Kiliyanur - Tindivanam - Vallam - Gingee - Pennathur - Tiruvannamalai - Pachal - Chengam - Singarapettai - Uthangarai - Samalpatti - Krishnagiri
References.
 ;templatestyles src="Reflist/styles.css" / ;