Idril was the daughter of Turgon of Gondolin. She was also named Celebrindal - "silver foot". She became the wife of Tuor, and thus became one of only three elves ever to marry a mortal man. Their son was named Eärendil.

The family escaped from Gondolin during its fall, and came eventually to Arvernien in the south of Beleriand - near the delta of the Sirion. There they lived until Tuor became old, and then both he and Idril set sail on board the ship Eärámë, journeying to the West.