Can anyone suggest me a book about the human willpower and survival in the face of unfathomable odds?

Basically any stories about human beings who have gone through and overcome incredibly difficult situations, whether physical, emotional etc. An example that comes to mind immediately is “unbroken”…but I want even more raw and desperate than that. The ultimate tale of human endurance in the face of grave resistance and opposition, whether man or nature. I am open to different genres of non fiction. Thank you.