Sea of Sorrows, but so long as you are on North American, it's fine. You could still join if you're on EU, but you won't be able to play with anyone. NA has better ping imho.
If you can, join Mists of Valhalla [MoV] :)
You can send anyone in that guild a message and they'll be able to get you invited. They're a great aussie guild, with AEST run events :)