Trysunda has its name from the great Scandinavian post-glacial rebound. Effectively, there was loads of ice (3 km thick) and everything got squeezed down a bit. Now the ice is gone and the land (mostly granite) bounces back. Makes perfect sense.
The island of Trysunda was actually three islands in the past. But since everything is bouncing around here, the land rose up and the three islands became one.
All fascinating stuff, but the most important thing is, that it is lovely.
Wot, no pics of the lovely Dreifaltigkeitsö?