Intihuatana is a ritual stone in Machu Picchu associated with the astronomic clock and calendar of the Inca. Its name is derived from the local Quechua language and it means “The Hitching Post of the Sun”. The stone is a wonder of their ancient technology. It’s a kind of clock that measures when it’s time to celebrate the winter solstice, called by the Incas INTI Raymi, one of the most important celebrations and rituals of the entire Empire. If you happen to be watching at noon on either equinox, you’ll notice the stone’s shadow disappear for just a moment, as designed by its creators.