I tried looking it up, I just have a feeling there is 1 mailbox in Deepholm, but I cannot find it anywhere (I am Horde) Could anyone confirm that there is or is not a mailbox?
There is a mailbox inside the Temple of Earth in the horde section...its in between the portal back to Orgrimmar and the portal up to Therazane's Throne.
When you enter from the front, theres a portal on the left for org, for horde, other hall past that portal are a few vendors and a mail box. It's the same on the other side of the cave for alliance, only the portal is sw.
at the temple of earth there is a mail box.
look the map of the temple of earth.
it is the main room and 2 wings
one yellow or open brownP
and one blue at the blue there is a mailbox
btw i would love if someone can tell me where is a mail box at uldum