The goblin-hall, or the great hall, was a large cavern in Goblin-town and the seat of the Great Goblin, its ruler, under the Misty Mountains.
The goblin-hall was rather large standing about one hundred feet high and three hundred feet long. At its eastern side stood a large platform where sat the Great Goblin until his death in July of 2941. It had only two ways in or out and was located about five miles from the Front Porch and about thirty miles from Gollum's cave.
History
The goblin-hall was the cavern where the Great Goblin briefly interrogated Thorin and Company for trespassing and possessing Elven weapons. It was also the place where Gandalf slew the Great Goblin after the Great Goblin had expressed that he would put them all to death.
Adaptions
The Hobbit: An Unexpected Journey
In Peter Jackson's The Hobbit: An Unexpected Journey, the Great Goblin's throne room is a cavern furnished of old timber, skeletons, rubbish and scavenged items.