The complex boasts a sun temple with a view of Machu Picchu and an observatory that marks the Pleiades constellation and the rising sun’s alignment at the equinoxes and summer solstice, important dates in the Incan agricultural seasons. The Incas ruled the Pacific Coast of South America and built a sophisticated system of roads and buildings that connected the empire. Spanish explorers annihilated the empire in the 1530s, using guns to defeat the Incan army.