section_path: Architecture/Principal construction types/E-Groups and observatories
section_name: E-Groups and observatories
paragraph_text: E-Groups and observatories
  
  The Maya were keen observers of the sun, stars, and planets. E-Groups were a particular arrangement of temples that were relatively common in the Maya region; they take their names from Group E at Uaxactun. They consisted of three small structures facing a fourth structure, and were used to mark the solstices and equinoxes. The earliest examples date to the Preclassic period. The Lost World complex at Tikal started out as an E-Group built towards the end of the Middle Preclassic. Due to its nature, the basic layout of an E-Group was constant. A structure was built on the west side of a plaza; it was usually a radial pyramid with stairways facing the cardinal directions. It faced east across the plaza to three small temples on the far side. From the west pyramid, the sun was seen to rise over these temples on the solstices and equinoxes. E-Groups were raised across the central and southern Maya area for over a millennium; not all were properly aligned as observatories, and their function may have been symbolic.
  
  As well as E-Groups, the Maya built other structures dedicated to observing the movements of celestial bodies. Many Maya buildings were aligned with astronomical bodies, including the planet Venus, and various constellations. The Caracol structure at Chichen Itza was a circular multi-level edifice, with a conical superstructure. It has slit windows that marked the movements of Venus. At Copán, a pair of stelae were raised to mark the position of the setting sun at the equinoxes.