A very large stone cairn (man-made pile of stones) in the Upper-Galilee, which up until now has been thought to simply be a retaining wall, was recently relabled as a Lunar Monument by Ido Wachtel, a PhD student at Jerusalem’s Hebrew University.

The enormous 5,000-year-old stone monument, shaped like a lunar crescent, is located near the Sea of Galilee and was originally thought to have been the retaining wall of a town or city. According to a report in Live Science the new attribution of the monument by Ido Wachtel came based upon new findings that Wachtel discerned from facts on the ground.

The crescent shape of the stone structure as well its proximity to the ancient town of Bet Yerah (‘House of the Moon’), known today as ‘Khirbet Kerak’, lead Wachtel to suggest that the structure was dedicated to the Akkadian Moon God, Sin, although its actual function is unknown.

The monument was found about 13 kilometers northwest of the Sea of Galilee making it over 29 kilometers from the town of Bet Yerah. In spite of the distance between the two, Wachtel still believes that the towns name lends evidence to the purpose of the cairn.

Bet Yerah was a large fortified city at the beginning of the third millennium BC. Its inhabitants traded with the early kings of Egypt, as seen from several artifacts, including a jug with a hieroglyphic inscription. The town spans an area of over 50 acres—one of the largest in the Levant.

The cairn consists of an enormous crescent-shaped mound of stones measuring about 150 meters in length, making it longer than an American or even Canadian football field. It is seven meters in height and has a volume of about 14,000 cubic meters.

Wachtel estimated that the construction of the monument would have taken between 35,000 and 50,000 days, thus taking 200 workers the better part of 5 months to complete. The site has been dated to between 3050 BCE and 2650 BCE based on pottery found in the structure, meaning it is likely older than the pyramids of Egypt and Stonehenge. However, it is unclear that the monument has any special astrological significance.

Aside from the pottery, no other artifacts or remains of buildings have been found in its vicinity, and the monument appears to be free standing.

“The proposed interpretation for the site is that it constituted a prominent landmark in its natural landscape, serving to mark possession and to assert authority and rights over natural resources by a local rural or pastoral population,” Wachtel wrote in the summary of a presentation given recently at the International Congress on the Archaeology of the Ancient Near East.

Today, people living in the area call the monument by its Arabic name, Rujum en-Nabi Shua’ayb, and it is sometimes referred to as the “Jethro Cairn,” a reference to the Druze prophet Jethro, who plays an important role in local folklore.

It is not the only stone structure or cairn to be found in the area. Other large rock structures have been found not far from the crescent-shaped monument. One structure, called Rujum el-Hiri, is located in the Golan Heights (east of the Sea of Galilee) and has four circles with a cairn at its center.

Another stone monument, a giant cairn that weighs more than 60,000 tons, was discovered recently beneath the waters of the Sea of Galilee. Its date is unknown, but like the crescent-shaped structure, it is located within close proximity to Bet Yerah.