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Sun-Earth Day Presents: Ancient Observatories, Timeless Knowledge

Technology Through Time: Issue #12, stonehenge

No one really knows what the creators of this monument had in mind when, over the course of three renovations spanning 1500 years, they built this famous ring of stones on a wind-swept hill.


Salisbury, England
Latitude, 51d 4' North
Longitude, 1d 48' West


This famous megalithic structure was apparently built in three stages beginning around 2950 B.C. and extending to 1600 B.C. During the first period of construction, it was a circular enclosure with two earthen banks and a ditch. During the second construction phase, about 2,000 BC, the inner circle of small bluestones, was set up, but abandoned before completion. The stones used in that first circle are believed to be from the Prescelly Mountains, located roughly 240 miles away, The bluestones weigh up to 4 tons each and about 80 stones were used, in all. Around 1600 BC, the outer ring of giant Sarsen Stones (as much as 50 tons each) were transported from the Marlborough Downs 20 miles to the north. It was originally thought that Stonehenge was built by ancient Druids, but this idea has been replaced by the idea that the late-Neolithic Becker People were probably the builders. Ancient Druids worshiped in forest temples and, presumably, had no need of stone constructions, according to some archeologists.


On the longest day of the year, the June 21st summer solstice, the rising sun appears behind the 'Heel Stone' - one of the main stones, creating the illusion that it is balancing on the stone. The Heel Stone sits along a wide lane called the Avenue. The rising Sun creeps up the length of the rock, creating a shadow that extends deep into the heart of five pairs of sarsen stone trilithons -- two pillar stones with one laid across the top -- in the shape of a horseshoe that opens up towards the rising sun. Archeoastronomers have also identified other stellar alignments with some of the other stones, however some controversy remains as to whether these stellar alignments were intended, or merely accidental.



Image Gallery:

stonehenge gallery image

Photo Credit:

Clive Ruggles

Technology Through Time Bulletin Board Activity

This bulletin board activity is designed to focus student attention on the role that sun watching has played in humankind's survival through time. As part of this display you may wish to use your own world map ordownload one we have created for you.

Related Stonehenge Links