Arrow Lake is a large lake in the foothills of The Barrier Mountains north of Antaur. Roughly triangular in shape, the lake has a number of small villages along its shoreline. Arrow Lake is known as Nendë Pilin in Elvish.
In the summer of 547UN (4145) a large flight of harpies moved down from the mountains over a period of months and took up residence in the cave system along the lakeshore. They were rooted out by a platoon from the 12th Division (The Bat) of Tirismálos led by Captain Castian Naeric and Lieutenant Aenwyn Doryra.