I'll second Old Man and the Sea
I'll nominate The Call of the Wild
by Jack London. Project Gutenberg link
Originally Posted by wiki
The Call of the Wild is a novella by American author Jack London published in 1903. The story takes place in the extreme conditions of the Yukon during the 19th-century Klondike Gold Rush, where strong sled dogs were in high demand. After Buck, a domesticated dog, is snatched from a pastoral ranch in California, he is sold into a brutal life as a sled dog. The novella details Buck's struggle to adjust and survive the cruel treatment he receives from humans, other dogs, and nature.