Fjallsárlón is a glacial lake at the south end of the Icelandic glacier Fjallsjökull, which is part of the larger glacier Vatnajökull. The better known glacier lake Jökulsárlón is not far from there. The famous volcano Öræfajökull looms above.

Beware of the skúas along the shore in the summertime, which aggressively protect their nests on the ground around the lake.