River Hrolleifsdalsá is in Hrolleifsdal that lies to the southeast of Tröllaskagafjallgarð. The valley is said to be named after the settler Hrolleifur. The river flows through the eastern part of Skagafjörður, about 18 km from the town Hofsós and just south of the churchyard Fell in Sléttuhlíð. This enjoyable fishing area offers very good char and brown trout fishing, and there is also the chance of salmon.