Hofsá is a river that runs through Vesturdalur in Skagafjörður, Iceland and joins the Vestari-Jökulsá where it flows out of Hofsdalur valley at Bjarnastaðahlíð, a short distance from the church site Goðadalir.

[1] The river is a spring creek that primarily comes from streams and lakes at the base of Hofsjökull glacier.

Although the water is glacier-colored after the Fossá flows into the river, which runs from Hofsjökull,[2] and flows somewhat inward within the area of the abandoned farm Þorljótsstaðir,[3] the river confluence is clear.

The name of the mountain slope east of the river is called Runa or Þorljótsstaðaruna, from which the river takes the name Runukvísl fork.

[4] There are excellent sites for trout fishing from there and all the way up to Runnfoss.