Guild Wars 2

I have just been killing a few things in Dredgehaunt Cliffs when i received the item Dwarven Key: Event Item. Can anyone tell me what this does or what its for? Thank You

http://wiki.guildwars2.com/wiki/Dwarven_Key

Thank you very much

Wiki is your friend. You can also use it in-game. You could have just typed /wiki dwarven key into the chat and your computer would have opened a browser to that page directly.