Lake Haedargardsvatn has an area of 0,15 km². It is quite deep and situated 16 m above sea level.

There is no sign of a surface catchment- or discharge areas. Road no. 204 takes you all the way to the lake shores and its surroundings are well vegetated and peaceful. The lake abounds in small brown trout, which was much larger, when the lake was netted. The best bait is said to be spinner.

The distance from the capital is about 260 km and 2 km from Kirkjubaejarklaustur.