For 10 points, name these Andean builders of Machu Picchu.
One palace built by this civilization is named for a twelve-angled stone in its walls. A three-stepped geometric design decorates a fountain with adjustable water flow at this civilization's Bath of the Princess. Thin films of water on two round, concave stones may have been used at one site by this empire's stargazers. On a peak overlooking that site, this empire's builders, who often employed the [*] Chakana symbol, engineered the sloping roof of the cave-enclosed Temple of the Moon. On the concentric depressed terraces of Moray, this empire's farmers experimented with strains of sweet potato, and a cathedral now stands on the site of their golden temple Coricancha. The Gate of the Sun, Intihuatana, and Condor Temple built by this empire were explored by Hiram Bingham. For 10 points, name these Andean builders of Machu Picchu.
One palace built by this civilization is named for a twelve-angled stone in its walls.
Incan Empire [or Tawantinsuyu]