Payaswini (Paachini in Tulu and local Malayalam) also known by the name Chandragiri is a river in Kasaragod district of Kerala state, south India. On the banks of this river is 17th century Chandragiri fort. This river is considered as the traditional boundary between Tulu Nadu and Malayalam regions of Kerala.The river originates in a village called Koinadu of Kodagu district in Karnataka state. It flows in a north-westerly direction through Sullia taluk of Dakshina Kannada district. In Sullia taluk, it is the major water source for domestic and agricultural purposes. It then flows west to Kasaragod district of Kerala state to join the Arabian sea.