Sasquatch in Washington has been a big deal since the 1920’s. There is an area in the foothills of Mount St. Helens called Ape Canyon. There are those who have tried to make it “Sasquatch Central” for years. I hiked St. Helens in the 1970’s (before the mountain blew its top) and toured the canyon after I learned of it. Pretty scenery but no ape men...
One of my kids’ favorite books that I would read to them was a goofy story about a Bigfoot that lived in lava tubes by Mount Saint Helens.
The Bigfoot rescues some kid lost in the forest, and I think the guy that hijacked the plane with the millions of dollars is also in that book. (Or at least his money is!)
https://www.amazon.com/Sasquatch-Roland-Smith/dp/0786813342#customerReviews
Heh - I think this must be the book!