Goblin Gate

The Back-door (also called the Goblin-gate) was a stone door on the eastern side of the Misty Mountains. It was used as a means of escape in the event of an emergency, and also as access to the lands beyond.
It could be reached by the tunnel that came from the Great Goblin's cavern and the one that came up from Gollum's cave. The room that it was located in was somewhat small in size.
== History ==
The door was evidently built by the Orcs when they tunneled out what was later called Goblin-town deep within the Misty Mountains, during their great increases in number between the years TA 2060 and TA 2480.
In the year TA 2941, Thorin and Company escaped the goblins through the back-door, shortly before Bilbo Baggins, pursued by Gollum, just managed to squeeze through the door, losing a few of his buttons in the process.