The Shire is a region of J. R. R. Tolkien's fictional Middle-earth, described in The Lord of the Rings and other works. The Shire refers to an area settled exclusively by Hobbits and largely removed from the goings-on in the rest of Middle-earth. It is located in the northwest of the continent, in the large region of Eriador and the Kingdom of Arnor.

Bag End was a luxurious smial (hobbit-burrow) built into the top of The Hill on the north side of Hobbiton. It was established by the Baggins family, whence its name Bag End, and it was their home for three generations, including Bilbo Baggins and Frodo Baggins. After the War of the Ring it passed to Sam Gamgee and his family.

"The Hobbit", the first well-known work set in Middle-earth, opens and closes in Bag End, as it does in "The Lord of the Rings". Bag End as a starting-point for adventure is referenced as 'the door where it began' in the song "The Road Goes Ever On".

Bag End was built by the wealthy and respected Bungo Baggins as a wedding gift for his bride Belladonna Took, one of numerous children of the Shire's Thain, the great Gerontius Took. Their son Bilbo inherited the smial in his adult bachelorhood on the death of his parents.

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