Ariyalur District is the youngest and most backward district in
Tamil Nadu. The district is bordered by the districts of
Cuddalore in the north,
Perambalur and
Tiruchirapalli in the west,
Thanjavur and
Tiruvarur in the south and
Nagapattinam in the east. It is considered to be the "Land of Fossils". Many prehistoric fossils are found in Ariyalur District. Recently, paleontologists have found a dinosaur's egg in Ariyalur. It has a population of about 1 million.