Check out this story about about a rock climber named Craig Armstrong and his pet cat named Millie. She goes everywhere he goes, including rock climbing excursions. According to Armstrong:
"I met Millie, my climbing partner, at Furburbia [an animal shelter in Utah]. We went into a tiny room to have a chat together away from all the other noisy campers. She climbed up my back and sat on my shoulders. It took about four seconds to realize we were now partners and would be going on many journeys together."
And journey they do:
Personally, I've always been really fascinated by people who take their cats with them on trips. One of my older friends used to be a truck driver, and he would take his cat with him on long drives. I have a monster of a Maine Coon mix, and while I've never taken him on a road trip, I'm certain he'd be a better companion than some humans I've traveled with.
You can read more about Millie and Craig here.