We should note that all of these places of thermal extremes (Finnish saunas, Japanese hot baths, American beaches and mountains) have their opposites close at hand. There are possibly two reasons for having the extremes right next to each other.
The first is physiological: the availability of extremes ensures that we can move from one to the other to maintain a thermal balance.
The second might be termed aesthetic: the experience of each extreme is made more acute by contrast to the other.
Works of art which have great life often have intense contrast within: rough/smooth, solid/void, loud/silent, empty/full. It is the difference between opposites which gives birth to something. Contrast is what often gives other principles their degree of life – the intensity of the boundary, the markedness of the alternating repetition.
Contrast strengthens centers by making each a deeper entity of itself, and thereby giving deeper meaning to both. It is, at its simplest, what allows us to differentiate. But meaningless contrast remains meaningless. It is only when centers are actively, mutually, and meaningfully composed that it acts to deepen the whole.
Le Corbusier, the greatest architect of the last century, noted that 'architecture is the learned game, correct and magnificent, of forms assembled in light', demonstrating to what extent light has been prioritized in the Western tradition. Tanizaki, on the other hand, spoke of the important of shadows, of extended eaves. Rather than the light that shines directly into a room, he praised the soft light that penetrates a space after being reflected off the floor, and again from the ceiling.
...In Japanese architecture, the gentle light that passes through shoji screens serves a key purpose. It reaches right to the back of the room, so that the space feels bright, even without the aid of artificial light. The soft light filtering through the white film at Takanawa Gateway Station represents a form of light that was forgotten about by Japanese Modernism.