Lake Bjarnarvatn has an area of 0,12 km² (Lake Mavsvatn 0,2 km²). They are situated 36 m and 18m above sea level.
Both lakes are rather shallow.
The lakes are barely accessible by 4wd vehicles. The catch consists mainly of rather large brown trout. The lakes were netted in the past.
The distance from the capital is about 775 km and 38 km from Thorshofn.