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Sun-Earth Day Presents: Ancient Observatories, Timeless Knowledge

Technology Through Time: Issue #4, Gotland Grooves

Thousands of groves, scattered on stones throughout the island of Gotland seem to connect the scattered parts together into a vast timepiece. Aligned with the sun, moon and stars, the grooves mark an ancient, human obsession with time and space over 3000 years ago.


Gotland, Sweden
Latitude 57.64N
Longitude 18.30E


There are about 3600 known grooves on stones scattered throughout the island of Gotland. 700 are scored directly into the limestone bedrock, the rest are found on about 800 stones. The length of the grooves varies from about 0.5 to 1 meter. They are between 5 cm to 10 cm wide and 1 cm to 10 cm in depth. The most important feature of the grooves appears to be in their alignment. A recent study of 1256 grooves showed that they are aligned with certain positions of the celestial bodies, apparently the sun or the moon. Most of them are oriented east to west.



Image Gallery:

Gotland Grooves gallery imageGotland Grooves gallery image

Photo Credit:

Soren Ganholm

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 Gotland Grooves Links

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