Bouldercrag's Refuge is founded by Earthen who has been banished from Earthen from Loken. You could come here under the quest of The Exiles of Ulduar. The entrance lies upside the Letter "T"(30,36) of the map mark" Snowdrift Plains". First open the route, binding your hearth Stone and then accept quest 2.
Deliver 2 and accept 3.4 .
Deliver 3.4, accept 5.6 .
Deliver 5.6, accept 7.8 .
When you are doing 7.8 at idavelir, Dark Armor Plate can be get from the drop of mobs, quest 9 will be activated.
Deliver 7.8.9, accept 10 .
There is a flying master at the lower right corner, please remember to open the route.