Bilbo Baggins reached the age of 111 at his birthday party in J.R.R. Tolkien’s The Fellowship of the Ring.
The party opens the novel’s prologue and first chapter, “A Long-Expected Party.” Bilbo’s birthday is celebrated on 22 September, the same date as Frodo Baggins’s birthday. Tolkien uses the hobbit expression “eleventy-first” for 111, giving the occasion a distinctive cultural flavor.
Bilbo’s longevity is unusual for a hobbit but not extraordinary by hobbit standards. He was born in 2890 of the Third Age, and the party takes place in 3001. During the celebration he gives a speech, disappears using the One Ring, and leaves Hobbiton for Rivendell.
The number is sometimes confused with Frodo’s age at the same party. Frodo turns 33, the age at which a hobbit comes of age. Bilbo’s party therefore marks two different milestones: Bilbo’s 111th birthday and Frodo’s 33rd.