Lake Thuridarvatn has an area of 1,2 km². Its greatest depth is 10,8 m and it is situated 416 m above sea level.
Its discharge, river Thuridara, tributes to the fine salmon river Hofsa. Road no. 85 passes the lake’s southeast corner. Its surroundings are bogs and tufted areas. The catch consists of lake char, ½-5 pounders.
The distance from the capital is 591 km and 25 km from Vopnafjordur.