Pinkuylluna was of great astronomical significance to the Incas. At dawn on the winter solstice the sun replaces the Pleiades at the left hand edge of the mountain. And, at the spring equinox the sun rises over the summit when seen from an observatory known as Incahuatana on the mountain above the terraces and Temple of the Sun. The buldings seen on Pinkuylluna are for food storage. Click image for larger photograph