 These Wildlife Sanctuaries are adjacent to the recently established Eravikulam National Park.The park area includes only reserve forest land, including Palni Hills Northern Slope East, Kallar, Palni Hills Southern Slope East, Upper Palni Shola, Allinagaram, and Palni Hills Northern Slope West Reserve Forests in the Dindigul 
and Kodaikanal Forest Divisions.The Palani Hills are formed of pre-Cambrian gneisses, charnockites and schists; they are among the oldest mountain ranges in India.