Its area is 3.4 km2 (1.3 sq mi), more than three times the size of Fjallavatn, the second largest lake, also located on Vágar.

The village of Miðvágur is closer to the lake than Sørvágur, but the latter is considered to have been settled earlier.

It is surrounded by a higher cliff which prevents it from emptying fully into the ocean, the waterfall Bøsdalafossur being the outlet.

The greater height of the cliffs on either side of Bøsdalafossur can give the illusion from certain perspectives that the lake is higher above sea level than it is.

[1] During World War II, the British army built an airfield (now Vágar Airport) to the west of the lake.