What John de Mandeville lacked in travel experience, he made up in imagination:
In Ethiope are such men that have but one foote, and they go so fast yt it is a great marvaill, & that is a large fote that the shadow thereof covereth ye body from son or rayne when they lye uppon their backes, and when their children be first borne they loke like russet, and when they waxe olde then they be all blacke.
The writer published a singular book full of such prodigies in the 14th century, most of it apparently borrowed from other writers or spun from whole cloth. Who would do such a thing? We’ll never know — as it turns out, the name “Mandeville” itself was made up.