Why Konbu hot springs in a forest.

While the name “Konbu Onsen” sounds strange, there are several theories as to why the term “konbu (seaweed)” is associated.
First, there is the theory that the Ainu people (indigenous people of Hokkaido) wrapped seaweed to trees to mark their way through the forest.
The other theory is that the fishers from Iwanai and the local farmers wrapped seaweed to a tree to mark the spot where they will engage in trading their respective goods from the sea and mountains. From then one, the phrase “to go to konbu” meant that trading was happening, and hence the region was named.
In addition, there is the theory that the phrase “Dokonbo Nupuli (meaning small hill in the Ainu language)” morphed into the current phrase, but so far no theory has been said to be concrete.