We spent the afternoon of January 10, 2012, visiting the UNESCO World Heritage Site (1983) of Machu Picchu. We were standing in the Sacred Plaza looking high up at the Intihuatana, one of the most important shrines at the site. The Intihuatana is a polygonal-shaped Sacred Stone (a.k.a. the Sundial) that was dedicated to the god Inti. The stone points directly at the sun during the winter solstice and is believed to be an astronomic clock built by the Incas. The stone is also called the Hitching Post of the Sun because legend says that it holds the sun in place. It was used in important Incan rituals and has become all the more important because it is one of the few Intihuatanas not destroyed by the Spanish conquistadores. Directly in front of us is the Principal Temple, a magnificent three-walled edifice that derives its name from its size and cleverly constructed foundation along with the beautiful stone work of its three main walls. The damage to the rear right corner is the result of the ground settling below this corner rather than any inherent weakness in the masonry itself (maybe too many tourists). Temperatures were in the low 70's with humid conditions.