The Einvigisfoss is a remote located waterfall en quit unknown. The waterfall is located south of Húnavatnshreppur at the end of road 722 (Vatnsdalsvegur) and is not an official named waterfall. The Einvigisfoss is named after the hillside that is called Einvigi.
On the west side of the river a dust road is running in the proximity of the river. I don’t know if it is possible to take the car but by foot is a 4,5 kilometer walk (60 minutes). On the way you will pass another waterfall called Ulfsfoss.