Lake Tritriva is a is small lake which fills an extinct crater 17 kilometres west of Antsirabe, past Lake Andraikiba. The name originates from the Malagasy words tritry, meaning the ridge back of a chameleon, and iva meaning deep. The lake is said to be some 80 metres deep.
As the water level drop in the rainy season and rise in the dry season debris from the lake can found down in a valley below, supporting a theory of existing underground channels.
According to local folklore, two interwoven trees at the lakeside represents a young couple so much in love they drowned themselves in the ice cold water as they were forbidden to marry by their respective families. If the branches are cut, blood, not sap, will ooze from the stems.