Tom, Bert, and William's cave

Tom, Bert, and William's cave was a cave under a hill in Eriador used by the trolls to hid from the Sunlight.

The cave was hidden by bushes and its entrance was locked by a heavy stone door which could only be open by a key.

The Hobbit
After the Tom, Bert, and William were turned to stone by the Sun, Thorin and Company followed the trolls markings up a hill and found the cave. At first they could not open it but Bilbo presented Gandalf with a large key which he used to open the door. They found the cave's interior filthy with bones on the floor and nasty smell; however, the cave was a treasure-filled all the troll's plunder. There was many Gold coins, brass buttons, and blades of various sizes and here Bilbo acquires the Elven-sword he named Sting, and Gandalf acquires the Elven-sword of Turgon, Glamdring. They were also clothes hanging on the walls that belonged to their victims. More useful to the group, was the mounts of fresh food and a barrel of ale still full. They buried the treasure near a river, which Gandalf set spells over so they would know where it was if they ever come back to recover it, and took the food.