The district of Ariyalur, formerly a part of Perambalur district was later bifurcated from Perambalur and started functioning separately from 23rd November 2007.
The district headquarters is located at Ariyalur. Ariyalur is rich with a number of historical locations and temples. The district is bordered by Cuddalore district in the north, Thanjavur district in the south and southeast, Trichy in the southwest, Nagapattinam in the east and Perambalur in the west. Ariyalur is located at a distance of 65 kilometers from Trichy.