On the way back from Gdansk, my father and I stopped in Szymbark to see its famous "house on the roof". The house was not as interesting as I expected it to be, but since it was on our way anyway, I do not regret that we went to see it.
The house on the roof:
In Szymbark you can also find Guiness World Records certified "world's longest piece of wood cut from a single tree":