In my novel A Woman in the Wild, the main character is Thea who goes to the mountains for a long retreat. The following passage is from one of her many hikes:

Photograph by Mykola Swarnyk, CC BY-SA 3.0, via Wikimedia Commons
She stopped in a small clearing to sip from her water flask. Above her, a stone’s throw away, a peregrine falcon perched on a thick branch. It looked like a lord of the valley, its eyes imperious as it surveyed the domains over which it could so easily soar. Beneath its dark hooked beak was a white bib of feathers and then the light and dark striations of its lower body. Watching, her head tilted upward, Thea felt the cool traces of the water slipping into her depths. After a few minutes she realized her expectation that the bird would take flight made no sense. To the falcon she was no more than a bush or a rock—earthbound, a slave of gravity.
Weaving among the trees, she ascended and followed the crest to the pine grove. She settled herself in the cloister of evergreens, her legs crossed and the needles soft beneath her. She breathed deeply until the air stretched her lungs. As she tried to empty her mind, she couldn’t help but think of the bear man. He had left everything behind. He was no longer the executive director of a nonprofit. His friends, his habits, and the life he had known, he had abandoned for the wild.
She had done much the same. She had left her practice. Her friends were like a footnote to the life she lived now.
The wind coursed through the boughs of the pines. She wanted that wind to clear her mind. She spent so much mental energy weaving thoughts of the bear man, Delphina, Hugh, and even Andreas. It was like making equations that hinted at a solution. The proper proportions, the correct configuration, the optimal order . . .
Think as she might, there were areas where she could not go. Not yet. She imagined the process like diving in a submersible, down mile after mile into the great trenches of the ocean. There, in the bright and artificial lights of that self-contained craft, she would discover inconceivable, multitudinous life forms thriving in the darkness of the abyss. She had already probed beneath the surface, but those depths six and seven miles down eluded her. She lacked the will. She lacked the heart. She couldn’t face the waters closing above her, the fading of the light as she made her lengthy descent, and the uncertainty of return.