Sundials - World's Oldest Clocks

North American Sundial Society


Sundial 94
State/Province:  Illinois Country:  USA
Dial Type:  Woodhenge Condition:  Good
Latitude:   38° 39.5592' N Longitude:   90° 4.4618' W
  • Cahokia Mounds State Historic Site, about a 20 minute drive from St. Louis. Take Interstate 55/70 East then very short distance South on Illinois Hwy 111, then East on Collinsville Rd. to visitor center
  • At the Cahokia Mounds is a woodhenge discovered in the early 1960's during excavations and has been reconstructed. There are a series of wood posts in multiple circles that indicate various solar events such as the solstices, equinoxes, and what are thought to be special festival days related to the agricultural cycle of the region. Critical posts also align with the mounds of the site on certain dates. The outer of 3 circles of posts has a diameter of 410 feet with 48 equidistant posts. Each post is about 20 feet high. Equinox and solstice sunrise observations are held at the site on the Sunday morning closest to the event.
General Information:
  • Owner: State of Illinois
  • Designer: Cahokia North American Indians
  • Builder: Cahokia North American Indians
  • Construction Date: circa 700-1400 A.D.
References: Web Links:
  • St. Louis Sundial Trail

Last Revised: 2018-01-27 12:46