There are many traditional Japanese things I have not tried but want to try.
One of them is called Goemon-buro. This is a bath tub where people take baths outside in the yard.
It is a special bath tub made out of cast iron. Water is warmed by direct flame with firewood. The tub of course gets really hot so you need to use a wood board. You balance yourself by standing on the board cutout. As you stand on it, you will start to sink down to the bottom. You don't want to fall over.
How nerve racking is that? You cannot even close your eyes to relax! That was what I was thinking while taking a hot bath with my eyes closed...
As a side note, Goemon (as pictured above) is a legendary bandit hero who stole gold and valuables and gave them to the poor, but I still have yet to research how they relate.