Before the Pyramids: Cracking Archaeology's Greatest Mystery (9 page)

Maybe, some experts have asserted, the henges were places where domestic animals could be corralled and kept safe from wild animals and would-be rustlers at night? Once again such a suggestion cannot apply to Thornborough, mostly on the grounds of the physical dimensions of the henges. Nobody would go to all the effort expended at Thornborough to protect a few sheep or cattle when a much smaller enclosure would have served the purpose far better. It is highly likely that animals were allowed into the henges – if only to keep the vegetation within them short, but this was clearly not their primary function.

What we are left with is the understandable fallback position of something that simply cannot be explained in terms of a practical use – namely a place of religion and ritual.

In this suggestion we may be approaching something like the truth. The three henges are connected, and probably always were, by a wide ‘avenue’. Such avenues are known to have existed elsewhere, for example at Stonehenge, and are thought to have been used at certain times of the year as processional routes from one part of a sacred landscape to another. Britain is also covered with long, usually straight, earthworks from early prehistory, known as ‘cursuses’.

If the giant henges at Thornborough and elsewhere seem to have proportions that are far larger than would be necessary for any human purpose, perhaps that is because they were never meant to be ‘human sized’ but rather ‘god sized’. It is also possible that they were so large on the landscape that it was thought by their creators that they were certain to be ‘seen’ by the gods, who were undoubtedly looking down on humanity from above. This theory is supported by the fact that the banks around the henges at Thornborough were once covered with a mineral called gypsum. This would have shone out brightly in sunlight or moonlight, though from the ground it would hardly have been discernible – especially as there is no high ground in the locality from which to view it. This massive undertaking in ‘lighting up’ the henges can surely only have been for the sake of the gods?

Of all the suggestions put forward by archaeologists to try and explain the existence and purpose of the Thornborough henges, only the ritual one makes any sense, though even this seemed to us to fall short of a total explanation for so much work.

So we asked ourselves, what were these henges for?

Given that they were planned using the Megalithic Yard and Rod, which are derived from timing the stars, it strongly suggested that astronomy must be of central importance. As we have said, the distance between the centres of the two outer henges is a curiously accurate 1,500 m, which we thought must be a coincidence. However, we were convinced that these structures were built for astronomical purposes, using astronomical techniques. So we wondered whether there was an astronomical factor in the layout – in terms of latitude and longitude.

The intelligence of the Neolithic people was no different than that of human beings today. Curious and thoughtful people could not help but notice how the heavens look different as one moves about from one geographical location to another. Any careful observer will quickly realize that the stars behave differently even over relatively small distances. As a person moves north or south, the point at which stars rise above the horizon changes. The further north one travels on the surface of Earth, the higher a given star will rise into the sky from the perspective of the observer. In addition, as a person moves east or west, the time of day of any stars rising changes. With accurate time-keeping (using a pendulum) it is possible to measure distance on the Earth’s surface (
see
figure 7). For a full explanation of how pendulums were used to measure a multitude of different astronomical happenings
see
Appendix 4.

If a Neolithic sky-watcher understood the culmination rule, he could erect a pole at two different places and gauge the difference in terms of Megalithic Degrees or seconds of arc. An archaeologist would quickly point out that because they ‘could’ have done something does not prove that they ‘did’, unless there are datable artefacts to support a claim. As these people did not have metals we are unlikely to find any tool that represents a modern sextant, but there are many ways to measure relative angles.

Figure 7.
A simple pendulum

But, even without unearthing a prehistoric sextant we can be sure that these henge builders could measure latitude from the stars.

When we checked the difference in latitude between the centres of the outer henges we found there is exactly 4 Msec of arc (41 × 366 MY) between them.

This was astonishing! The accuracy of measurement is simply incredible, given that the Megalithic Second of arc is the smallest unit of geometric division apart from the Megalithic Yard itself, but the facts speak for themselves. Highly competent astronomers built these Neolithic structures. We were at a loss to understand how they could have measured such fine differences in latitude – but it seemed that somehow they did.

Next we pulled back to take in the bigger picture. Given the science that we could now see underpins the entire site of these gigantic structures we needed to consider why the people creating them had constructed a slightly bent alignment and built them with openings to each henge along an avenue pointing approximately northwest to southeast.

The first thing that is obvious is that the site is remarkably flat with only a very gentle slope from north to south. There are no large hills in the vicinity and so the view to all sides of the henges is unobstructed. There are hills in the distance, especially to the east, but when the banks were fully in place these would have been obscured. All heavenly bodies seen from the centre of any of the henges would rise from and fall back to the top of the banks, and there are no reference points on the horizon as are found at many stone circles. This is because from inside the henges there are no natural horizons to be seen, except through the deliberately engineered openings.

The location of the Thornborough henges is unusual in a British upland context because there are no hills of note for a staggering 127. 9 km (79.5 miles) to the southeast; the first being the 77 m-high hill upon which Lincoln Cathedral now stands. Strangely, the angle of the central and southern henges, their openings and the avenue, all point like a gun sight in the direction of the Lincoln mound. We could not think of any other location in the British Isles that delivers up such a long stretch of almost flat land. This seemed unlikely to be coincidence.

But what function could this virtual sightline serve? The curvature of the Earth makes it impossible to see such a distance but is there something significant about the location of Lincoln Cathedral? We were well aware that churches were often built on the ancient ‘holy’ sites from prehistory. Indeed, the tallest megalithic standing stone in Britain, with a height of 8 m and a circumference of 5 m, stands next to an old church in the village of Rudston, close to where Alan lives. The church and its graveyard were built inside Neolithic earthworks.

The distance between the centre of the southern Thornborough henge and the highest point at Lincoln is 127.13 km, which does not convert to any apparently meaningful distance in megalithic units. It was obvious that these Neolithic people could never have measured such a distance across the ground, using ropes for example, because every rise and fall would completely distort the result – even if they found a way to measure across rivers they would end up with a meaningless figure. But it occurred to Chris that they could use astronomy very accurately to measure relative latitude – the distance between two points on the Earth’s surface in terms of the north to south divide.

Figure 8.
Thornborough henges circa 3500
BC

Using Google Earth, Chris carefully measured from the centre of the middle Thornborough henge to a point on the same latitude as the Lincoln mound, following the longitude of the henge centre to establish the north–south distance. The result was almost beyond belief.

The two places are exactly 1 Megalithic Degree of latitude apart – which means that they mark out 1/366th of the polar circumference of the Earth.

Simply stunning! This level of information changes everything we thought we knew about Thornborough – and about the extent of Neolithic scientific ability.

Out of curiosity Chris next projected the line in the opposite direction from the central henge through the northern henge, but here it crosses large hills and mountains. Nevertheless he continued the line across the Scottish mountains until it hit the Atlantic – very close to the Isle of Lewis.

Knowing that the beautifully preserved Megalithic stone circle of Callanish was on this northern island Chris measured the distance from the circle back down to Thornborough. The line from the Callanish circle to the centre of Thornborough is a rather meaningless 546,488 m, but when converted to Megalithic units it looks very interesting:

 546,488 m = 658,689 MY

When divided by 366 × 360, to express the distance in Megalithic Degrees, the result is 5 Megalithic Degrees. A coincidence? We choose to make a decision based upon the evidence rather than on any preconceived ideas about intelligence or technical abilities of the inhabitants of the British Isles 5,500 years ago.

This prompted a question of whether or not the location of the Thornborough henges is geographically significant in any really fundamental way. A quick check revealed that these henges stand on a very significant latitude. To a very high degree of accuracy they are placed at a point that is 1/10th of the planet’s circumference from the North Pole!

The group behind these henges must have made measurements up and down the length of the British Isles – and maybe further – before they discovered that the area now called Thornborough is very special indeed. In addition to the henges and their flat sightlines we went on to discover yet more reasons why this location would have been meaningful for the architects concerned.

For the Neolithic peoples, Sirius, as the brightest star in the night sky, was almost certainly considered to be the chief object of the fixed heavens. It just so happens that Sirius was part of a very unusual relationship when viewed from the latitude of Thornborough. At the point in history that the Thornborough henges were built (circa 3500
BC
), Sirius rose and set at the same point on the horizon as the Sun at the winter solstice (then 18 January) – this was almost exactly SE and SW. Such a happening must have created the impression that Sirius was linked in some way with the Sun when observed from Thornborough. At this location the Stone Age astronomers could witness the star apparently stopping the Sun’s progress across the horizon from north to south. (At midwinter when viewed from the northern hemisphere the Sun rises as far south as it ever does. The days are short, the weather cold and nature effectively dead. If the Sun cannot be prevented from travelling even further south then surely death and destruction must be the result.) From Thornborough it appeared that the great star Sirius halted the Sun’s southern progress and persuaded it to begin moving northwards again, towards summer and a time of plenty. To Stone Age farmers this must have seemed crucially important.

They would have realized that Sirius (like all stars) passed over their heads once per day and a total of 366 times per year. One can imagine that this would have prompted them to divide the circle of the day into 366 parts – which in another sense can be seen as 366 divisions (or degrees) of the sky. They could achieve this by creating a henge and dividing the circle of the banks into 366 parts. They would designate the divisions or degrees with thin poles pushed into the bank tops to mark out the width of one degree. With these in place the astronomer-priests could observe the movement of the stars across the horizon. To measure rising stars, such as Sirius, they would have made a frame – one-degree square as seen from the centre of the henge – and they would then have tilted it so that Sirius rose vertically in relation to the frame. In the case of Sirius this experiment was most probably done at the autumn equinox when Sirius was easiest to see.