Because the markings on the moon look somewhat like a human face, this has inspired legends and folklore. Follow the link for a compendium of Moon Folklore featuring the Man in the Moon.
In ancient Greece there was speculation on whether the moon was inhabited. Anaxagoras thought there were buildings on the moon, buildings implying inhabitants. Both Leonardo da Vinci and Herschel shared this opinion. Nor must one forget, in this context, von Gruithuizen (1774-1852), who claimed to have observed a lunar city.