Eithel Sirion was the source of the River Sirion in the Ered Wethrin. It was in the pass overlooking this spot that Fëanor died after being mortally wounded by Gothmog the Balrog.

In later years Fingolfin built the fortress of Barad Eithel in the same location to look out across Ard Galen towards Thangorodrim. It was attacked several times and finally fell at Nirnaeth Arnoediad when Fingon was killed.