Board Thread:General Discussion/@comment-25355646-20150313022728/@comment-25926288-20150313023545

Clearly it's the Charmed Ones hideout.

It may simply be the "Northern Kingdom" that we've never seen, a random kingdom that houses its prized Tree of Wisdom, or it's Midgard, or a Norse kingdom separated from Arendelle. Or maybe it belongs to a small kingdom or private landowner that guards it.