Uaxactún

Uaxactún lies just 16 miles from Tikal, its rival city in ancient Maya times.



Uaxactún, which means "eight-stone" in Yucatec Maya and is named for the earliest stela found there (dated to A.D. 328), is one of the most intensively studied Maya sites. The ceramic sequence that came out of early work there provided the basis for the entire Maya lowland chronology. One of the most notable series of buildings at the site is that formed by Structures E-1, E-2, and E-3, which are aligned north-south and form an astronomical observatory, the first found in the Maya world. From a observation point on a nearby pyramid, the early Maya could watch the sun rise behind these buildings and mark the summer and winter solstices (the longest and shortest days of the year) as well as the vernal and autumnal equinoxes (when day and night are of equal length).



Source: http://www.pbs.org/wgbh/nova/maya/worl_sans3_03.html