Through most of history, people have been closely tied to nature, hunting in forests and having an intimate knowledge of the animals in their regions. So-called "primitive" peoples were walking encyclopedias of the natural world, and yet most believed there were more creatures lurking in those woods than the ones they usually encountered.

In North America, the most debated subject in cryptozoology concerns the existence (or otherwise) of a large, unknown hominid inhabiting the Pacific Northwest of the United States and Canada's West Coast. For many skeptics, this is nothing more than a woodland fairy tale that illustrates the credulity of believers, because they believe it would be impossible for such a creature to exist in a country as heavily populated as the United States yet remain completely unknown to mainstream zoologists. On the face of it, that seems a fair contention, since other large creatures such as bears, mountain lions, elk and many others live in the region. Biologists have been able to study these animals in the wild, to recover remains of dead animals, and even live specimens, but while a great many people have looked, to date, no one has been able to capture a Bigfoot or to find remains or other physical evidence such as hair that can be definitively shown to have come from an unknown hominid. That certainly seems to support the skeptics' case.

Nonetheless, sensible, knowledgeable, and seemingly witnesses continue to make sightings of something very large and odd in the vast forests of the Pacific Northwest. There is even tantalizing scientific evidence that suggests Bigfoot is something more than just a campfire tale. While these sightings are typically dismissed as errors or delusions and that all physical evidence thus far, such as footprints, have been hoaxes, fervent believers are still out there claiming that Bigfoot does indeed exist.