The Westfjords or West Fjords (Icelandic: Vestfirðir) is a large peninsula in northwestern Iceland and an administrative district.
The Westfjords are very mountainous; the coastline is heavily indented by dozens of fjords surrounded by steep hills.
Don't know for sure if Þingmannafoss is the proper name for this waterfall, I can't find the name on any maps, however the river is called Þingmannaá...