Hirilorn
The Hirilorn tree was located in Doriath. It was near the gates of Menegroth. It was extremely tall and King Thingol of Doriath built his throne room at its highest branch. In 465 of the First Age, Thingol locked his daughter Luthien in his throne room so she could not rescue Beren. The staircases were taken away. Luthien grew her hair and was able escape Hirilorn and she saved Beren, who later died at Hirilorn.