Wednesday, October 21, 2015

Pathways for the Sun – Britain’s Neolithic Monuments

By Lynne Kristine Thorsen

Ah, the sky. The sun signals the return of seasons. The stars provide direction. The moon is a harbinger of events, a teller of tales. We see so little of the celestial secrets today. But eons ago, the signals from the sky meant everything.

Consider the sun. With its warmth comes the seasons of planting, of fecundity. How could we, as early agronomists, know when to plant, know when the seasons would begin to change? And once we had that knowledge, how could we celebrate that change and encourage its continuation?

I started considering these questions the first time I saw Silbury Hill. It was in late June in 1991 and it was my first visit back to England in years. Silbury Hill is really quite startling. It’s obviously man-made and huge. It is part of the Avebury and Kennet Long Barrow group of Neolithic monuments. The day was drizzly and overcast, and I remember just standing and staring at the hill.

Silbury Hill

Silbury Hill is part of the neolith monuments around Avebury in Wiltshire, Britain. It is the tallest human-made prehistoric mound in Europe. Its construction dates to around 2500 BC, and calculations suggest it may have taken 500 men working for 15 years to deposit and shape the chalk and clay that it’s made from. It’s a mound. No tunnels have been found. It took technical skill and an amazing amount of labor to create this structure. It must have meant something.

Farming reached Britain around 4500 BC. It has been calculated that it took around 2000 years before farming spread across most parts of the British Isles. The advent of an agrarian society meant that people stayed pretty much where they were. They build settlements, defenses, and with agriculture, discovered new gods.

So, what does Silbury Hill look like? A mound -- a swollen belly – a pregnant earth? What could be more life-bringing than to actually see the earth as a pregnant source about to give birth to crops, to domesticated animals, to their own young. What could be a more important blessing – a visual prayer?

As crops took on a more important role so did ensuring, by whatever method they could, the best harvest. There was now time to consider how to best support this new lifestyle, how to more clearly celebrate and encourage its continuance. Something permanent and predictive was needed. Between 3200 B.C. and 2500 B.C., elaborate mounds with chambered central rooms and passageways were constructed all over Britain.


Maeshowe is a Neolithic chambered cairn in the Orkney Islands. It is referred to as a burial tomb because a skull was found during early excavation. It was constructed around 2800 BC. The mound is 115 feet in diameter and rises to a height of 24 feet. There is a 45 foot long ditch that leads to the chambered mound. There is an entrance passage that is 36 feet long and leads to the central almost square chamber measuring about 15 feet on each side. The current height of the chamber is 12.5 feet high. The central chambers are built of carefully crafted slabs of flagstone weighing up to 30 tons each. Estimates of the amount of effort required to construct the cairn range from 39,000 to 100,000 man hours. That’s a lot of time.

Maeshowe Passage
Courtesy of Rob Burke
Creative Commons
Here’s the interesting bit. The mound is aligned so that the rear wall of its central chamber is illuminated during the winter solstice as the solstice sun passes down the entrance passage and into the chamber. So, not only did they have the manpower, drive, and technology to construct the cairn, they also had the calendric knowledge to allow it to serve as a signifier of the turning of the seasons, which clearly was of high significance for them.

A similar display occurs in Newgrange.


Newgrange is a prehistoric monument in County Meath, Ireland. It is also referred to as a passage tomb because of human bone fragments and ash that were found during the various excavations. It was built in the Neolithic period around 3200 BC, making it one of the oldest monuments of its kind. The site consists of a large circular mound with a stone passageway and interior chambers. The mound has a retaining wall at the front and is ringed by engraved kerbstones.

The mound is 249 ft across and 39 ft high. Within the mound is a chambered passage, which can be accessed by an entrance on the southeastern side of the monument. The passage stretches for 60 ft or about a third of the way into the center of the structure. At the end of the passage are three small chambers off a larger central chamber, with a high vault roof. It is estimated that it would have taken a workforce of 300 men 30 years to construct the monument.

Lit passage way during the
winter solstice at Newgrange

Courtesy of Dentp at Wikimedia
As with Maeshowe, once a year at the winter solstice, the rising sun shines directly along the long passage, illuminating the inner chamber and revealing the carvings inside, notably the spiral on the front wall of the chamber. This illumination lasts for about 17 minutes. Considerable planning and technical skill were required to construct this spectacular site.

And again, a similar observation, but this time during the summer solstice, is found at Bryn Celli Ddu on the Welsh island of Anglesey.

Bryn Celli Ddu

Maes Howe Burial Chamber
Photo courtesy of Stephen McKay
Creative Commons
Bryn Celli Ddu is a stone-chambered prehistoric monument on Anglesey in Wales. Again, it is generally referred to as a passage tomb. Bryn Celli Ddu was built with a complete passage and chamber that is buried under a mound or cairn. As it now stands, the passage is 28 ft long. The first 11 feet of the passage are not roofed. The formal entrance is flanked by a pair of portal stones.

The oldest archeological evidence from the site are ashes from postholes that date to 4000 B.C. These are thought to be the remnants of a wooden henge. Around 1000 years later, a stone henge supplanted the original wooden one. The passage monument followed, constructed around 2000 B.C.

Several unusual stones are at the site. Inside the burial chamber is a free-standing six foot high smooth stone pillar with a very rounded shape, which is quite rare.

Bryn Celli Ddu is accurately aligned to coincide with the rising sun on the longest day of the year. At dawn on midsummer solstice, shafts of light from the rising sun penetrate down the passageway to light the inner chamber. Norman Lockyer, who published the first systematic study of megalithic astronomy, was the first to notice the alignment. Later research conducted in 1997-1998 provided evidence that the site contained year-round alignments which allowed the site to be used as an agricultural calendar.

Bryn Celli Ddu
Courtesy of Wolfgang Sauber
Creative Commons

Precession of the Sun

These three separate illustrations of British Neolithic monuments designed as designators of the solstice of the seasons represent a few of the larger, more recognizable agrarian calendars. One can imagine that these sites were ceremonial, with displays and rituals to formally recognize the seasons. And one can just as easily imagine that there were many more sites with similar displays for smaller more remote communities that are no longer available. Many have been destroyed or forgotten. But some still standing may no longer function as a solar calendar.

During a full year, the sun traces a path through the stars known as the ecliptic. Anyone investigating possible architectural alignments upon the sun, moon, or planets would need to take into account the way the obliquity of the ecliptic of the sun changes over the centuries.

The last five thousand years represent a small segment of this cycle of the sun. During this time the obliquity has been gradually decreasing. One practical effect of this is that the ranges over which the rising and setting position of the sun swings during the year were somewhat wider in, say, Neolithic times. In particular, the rising and setting positions of the sun at the solstices were about one degree (two solar diameters) further away from each other then than now. In a more straightforward manner this means that smaller solstice markers would not mark the solstice today because of the difference of the position of the sun today as opposed to 5,000 years ago.

Not Burial Tombs

Significant time and effort created these monuments and many others like them. Ancient observers of the position of the sun as it related to the change of seasons knew, down to the minute, when the seasonal changes occurred. It was clearly important, extremely meaningful to their daily life, and needed to be consecrated in stone, in an immovable monument that would serve as a signifier for the ages to come.

Within and around these monuments, rituals would be performed and traditions passed down. And what could be more symbolic than a monument to the womb of the earth with a birth canal that leads out from the interior of the earth to the light of the sun. Imagine the shamans waiting inside the chamber for the solstice sun and then emerging, through the passage as if reborn, into the light of day.

It seems to be a world-wide practice among many archaeologists and laymen to label any historic puzzle that is not understood with the words, “It must have been religious.” And we tend to put our modern beliefs on top of past ritualistic sites that we don’t understand. “Oh, there are bones and ashes. It must be a tomb.” We believe in ritualistic burial, so they must have.

For me, a few bones and ashes do not turn these amazing structures into a place for the dead. It would be more appropriate to say, “Oh this was an example of their extraordinary research, science, and architecture.”

This could just be an argument about semantics. But, it illustrates a very important point, which is, as we approach the past we must discard the prejudices of the present. We need to reach back, as much as we can, and consider what their primary considerations might have been and how these considerations informed their lives and their landscape.


Ancient Astronomy, Obliquity of the ecliptic
Silbury Hill – Council for British Archeology, English Heritage, Wikipedia
Newgrange – World Heritage Ireland, Newgrange Stone Age Passage Tomb, Wikipedia
Maeshowe – Orkney’s finest chambered cairn, Wikipedia, A spectacular Neolithic chambered cairn
Bryn Celli Ddu – Cadw Welsh Government, Stones of Wales, Ancient Wisdom, Wikipedia


Lynn Kristine Thorsen’s two short story collections, “Fever Dreams” and “Mischief” will be published later this fall. She is also hard at work on an Elizabethan novel. She enjoys travel in Northern Wales, castles, the American Southwest, and good fiction.


  1. I find these places fascinating. I've written about Silbury Hill, and I've been to Bryn Celli Ddu (I also can be found often exploring North Wales) but the one I'd really like to visit is Newgrange. Thanks for posting :)

    1. So glad you enjoyed it! I love Northern Wales -- love the sense of history and the beauty of the country. I was very drawn to these Neolithic sites and really enjoyed exploring what they might mean. Cheers!

  2. Wow very insightful, I really wanna go and see newgrange so badly

    1. I've been wanting to write about these sites for quite a while, so this was a great opportunity. Plan a trip to Newgrange!



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