Lake Langavatn in Skagahreppur in Austur-Húnavatnssýsla is the largest lake in the western part of Skaga. It is 3.5 km² in area, shallow and at 207 m above sea level. Fjallabaksá flows into it at its southern end and Langavatnsá flows from it through Skjaldbreiðurvatn and on to the sea. The lower reaches of the river is called Fossá and it plunges from Króksbjarg into the sea. There are a lot of good fish in the lake, both brown trout and Arctic char, with the largest 1-3 pounds. There has been a lot of net fishing in Langavatn, which helps to keep the size of the fish in balance. Good fishing spots are from two peninsulas on the south and north coast. It is also productive to fish where streams flow into the lake, e.g. ahead of Þórhildardalslækur and Fjallabaksá.