A yang light shining down into the dark yin valley. While this scene is imaginary it reminds me of Opabin Pass, below Mount Biddle in Yoho National Park.

Perhaps this image is something, perhaps nothing.
To give some clues I offer:
The following part of the Tao Te Ching
as translated
by Henry Wei in his book
The Guiding Light of Lao Tzu.

'The spirit of the valley never dies,
Hence comes the name Mysterious Female.
The gateway of the Mysterious Female
Is the root of Heaven and Earth.
Continuous like a thread it seems to exist,
Its utility is inexaustible"