A huge early Celtic calendar construction has been discovered in the royal tomb of Magdalenenberg, nearby Villingen-Schwenningen in the Black Forest. This discovery was made by researchers at the Römisch-GermanischesPress Zentralmuseum at Mainz in Germany when they evaluated old excavation plans. The order of the burials around the central royal tomb fits exactly with the sky constellations of the Northern hemisphere.

General plan of the early Celtic burial mound with sky constellations [Credit: Image courtesy of Römisch-Germanisches Zentralmuseum]

Whereas Stonehenge was orientated towards the sun, the more then 100 meter width burial mound of Magdalenenberg was focused towards the moon. The builders positioned long rows of wooden posts in the burial mound to be able to focus on the Lunar Standstills. These Lunar Standstills happen every 18,6 year and were the ‘corner stones’ of the Celtic calendar.

The position of the burials at Magdeleneberg represents a constellation pattern which can be seen between Midwinter and Midsummer. With the help of special computer programs, Dr. Allard Mees, researcher at the Römisch-Germanischen Zentralmuseum, could reconstruct the position of the sky constellations in the early Celtic period and following from that those which were visible at Midsummer. This archaeo-astronomic research resulted in a date of Midsummer 618 BC, which makes it the earliest and most complete example of a Celtic calendar focused on the moon.