Ytra-Deildarvatn is on the east side of Melrakkaslétta. It is 1.3 km² in area, rather shallow and at 38 m above sea level. The Fremri-Deildará, Ölduá and various other streams flow into it. Deildará, which is a nice salmon river, flows from the lake to the sea. In Ytra Deildarvatn there is good fishing, mostly brown trout but also some Arctic char. From the main road to Ytra-Deildarvatn is 4.5 km and it is possible to drive to it from two places, by the airport just east of the lake and from the farm Hólar.