Bilbo Baggins is 111 years old when he leaves the Shire in J.R.R. Tolkien’s The Lord of the Rings.
Bilbo’s birthday is 22 September, and his eleventy-first birthday is the occasion for the famous party at Hobbiton. During the celebration, he gives a speech, uses the One Ring to disappear, and leaves the Shire for Rivendell. The departure begins the opening movement of The Fellowship of the Ring.
Bilbo had already undertaken his adventure in The Hobbit, where he was much younger. By the time of his later birthday, he has possessed the Ring for decades and has remained unusually vigorous, a condition linked to the Ring’s influence.
“Eleventy-first” means 111th, not 101st or 110th. Bilbo’s party is also the event at which he publicly passes Bag End and the Ring to Frodo, although he initially struggles emotionally to surrender the Ring completely.