The Kalvarayan Hills are a major range of hills situated in the Eastern Ghats of the southern Indian state of Tamil Nadu. Along with the Pachaimalai, Alavaimalai, Javadi, and Shevaroy hills, they separate the Kaveri River basin to the south from the Palar River basin to the north. The hills range in height from 2000 feet to 3000 feet and extend over an area of 1095 square kilometres.