During some construction efforts to place a fourth oven at the Party Tree, a shovel scraped against something wooden buried in the hillside. The oven was quickly forgotten, and an excavation of a door came to pass instead.
NOTE: This quest will be removed from your quest log when the event it is associated with ends.
'You'll never believe this, ${PLAYER}! I decided a new oven was needed to begin preparations for the next festival. The labourers went to dig a pit into the side of the Hill, and lo! We all heard a shovel scrape against some wood, and before I knew what happened, a door was dug out!
'The door is locked now, but I'll wager it is a forgotten cellar of Bag End. Bag End is just above it, you see. Do you think that's where Mad Baggins kept his treasures? I suppose we can only guess...for Lobelia owns Bag End now.
'If you think she'll be letting anyone else dig around for Old Bilbo's treasure, then you go right ahead and ask her; be my guest! I won't be risking it...but it is terribly exciting, all the same!'
Lobelia Sackville-Baggins is at Bag End, north and up the Hill from the Party Tree.
You should speak with Lobelia if you are interested in getting into the newly excavated door, likely leading into a hidden cellar of Bag End.
You seem to recall that Bilbo and Frodo, the last proprietors of Bag End, were good friends with the Gamgees on Bagshot Row, south of Bag End, just below the Party Tree.
You should speak with Hamfast Gamgee, otherwise known as the Gaffer, to see if Bilbo or Frodo left him any clues as to the whereabouts of a key to the secret cellar.