Lake Leirvogsvatn has an area of 1,2 km², its deepest point is 16 m and it is situated 211 m above mean sea level. It is by the main road (36) between the capital and the historical site „The Parliamentary Plains” (Žingvellir). Its discharge is the good salmon river Leirvogsa. The lake abounds in lake char and brown trout.

According to legends, there was a horse shaped monster with reversed hoofs in the lake. Amazingly enough such monsters seem to have disappeared from all Icelandic lakes and become extinct not too long ago. The excitement of angling has to suffice nowadays.

The distance from the capital is about 30 km.