For centuries, findings of large fossilized bones of extinct animals triggered the imagination of humans all over the world. People were curious about the origin of these enormous bones. They created, what from our point of view appear to be, monsterous reconstructions of beings to which the bones may have once belonged. People believed that the bones belonged to a number of different types of monsters. The very fact that such reconstructions were made is not as unusual as it may appear. Even now findings of large bones trigger the imagination. Thanks to our increased knowledge of the anatomy and ecology of these extinct beasts, we can now make more realistic reconstructions than ever before. This article deals mainly with the findings of Pleistocene mammalian bones and the way people through the ages perceived them.