Vellayani Lake is a fresh water lake, which is located in the Thiruvananthapuram District of Kerala. Covering an area of 7.5 sq km, this lake is the largest freshwater lake in Thiruvananthapuram District. Many people visit this lake during moonlit nights. Vellayani Lake attracts large number of tourists during Onam, when the boat race is held in the lake. Located about 7 km away from Kovalam, this lake can be reached by hiring country boats from Kovalam Beach.