Interesting picture (by Kim Nilsson) of one of the Överhogdal tapestries.
In the center, you can easily identify Yggdrasil, the 'World Tree' in the Norse mythology/mysticism.
You can also spot an eight-legged horse, which might be Sleipnir, Odin's steed.
This tapestry has been dated between 800 and 110 A.D.