So Yggdrasil, it is very atmospheric, very nature oriented. In this album the lyrics are written in Norwegian, Old Norse and Proto-Norse tongue, and sounds like trees, rocks, water and torches are also used. it is very relaxing and never disturbing, very introspective, but you really have to be in the mood for it, or you will find it rather boring. It may be described as folk, but it is not just folk really, you really need to hear it all, the whispering (and intimidating) voices, and all the ambience they create, so you can really understand what it is about.
The album has 11 tracks, all similar in their composition, and it's a very calm, really hard to describe in words, so if this is your kind of thing, go for it, and come to your own conclusions.