This photo (right) was supplied by Crispian Oates. It shows the central and northern (tree covered) henges at Thornborough. It also shows the effects of recent quarrying - The blue lakes left by Thornborough and Nosterfield Quarry's. Dominating an area over a mile in extent, the ancient monument complex at Thornborough is one of Britain's most important ancient sites. Described by English Heritage as the most important ancient site between Stonehenge and the Orkneys, many people are amazed to learn that an ancient site that rivals Stonehenge is located in North Yorkshire, close to Ripon. To understand just how special Thornborough is, one must realise that it is the central site in a complex of ancient monuments that create a 5,000 year old sacred landscape over twenty miles in extent - comprising of some of the largest ancient structures in Britain the "Sacred Vale" is Britain's greatest Neolithic complex, and Thornborough is its largest site - a complex in itself. Thornborough is so a large site that it must have drawn people from miles around. At a time when the population of Britain is estimated to be a couple of hundred thousand at best, the gatherings at Thornborough may well have been the largest seen in Britain. At its peak in c. 3,000BC Thornborough was the equivalent of three massive cathedrals, each 240m in diameter. Even with the recent quarrying, Thornborough is still one of the best preserved henge sites in Britain, the now tree covered Northern Henge is Britain's best preserved henge. Photo: Above - Crispian Oates, Thornborough Southern Henge. Below - Crispian Oates, Thornborough Henges. Comparing Thornborough to Stonehenge serves to emphasise the stature of this ancient temple. The stones at Stonehenge are approximately 40m in diameter. These are surrounded by an earlier circular earth bank with external ditch - this is the henge, it is c. 90m in diameter and represents the largest enclosed space created on the site. Thornborough is a single site with three identical circular henges, each a mighty 240m in diameter - the stone circle at Stonehenge could fit within each of Thornborough's rings more than ten times over without touching. The Thornborough Henges are a unique triple 'super-henge' monument of identical components. If the henges were used simultaneously it would be Britain's largest ritual site. Thornborough does not simply consist of the henges, there are a great many other monuments that make up this ritual site. These include cursuses, enclosures, burial sites, settlements and intriguing pit alignments. Thornborough was seen as a place of spiritual importance for more than 4,000 years until at least the Roman period. The monuments of later years, whilst almost all are barely visible today are no less interesting than the henges themselves, for each tells an important story of man's relationship with the henges and provide vital clues about what the henges were for and those that used them. For example, in one location was recently uncovered a late Iron Age burial ground, this comprised of two square barrows on the edge of a cemetery in use since the early Bronze Age. This extremely rare find, linked with a nearby four horse burial, shows that even in the late Iron Age, Thornborough's fame still spread across tribal boundaries and was a place steeped in the religion of the day. Furthermore, Thornborough is possibly one of the worlds first major astronomically based monuments. Underneath the central henge is the Thornborough Cursus (c. 3,500BC), this 1.2km long "ritual walkway" is possibly the first monument in the world aligned to the Orion constellation, a pattern remembered in the construction of the henges, which mirror Orion's Belt. Photos: Left - Square barrow on Nosterfield Quarry. Right - Thornborough Henges and pit alignments supplied by Sacred Vale. Britain's foremost expert on Thornborough is Dr Jan (Yan) Harding of Newcastle University, spent ten years researching Thornborough and has put together an extensive website. Dr Harding has suggested that the henge complex at Thornborough was possibly the most important ritual site during its period of use. Dr Mark Horton, Head of Archaeology at Bristol University and presenter of the BBC TV programme Time Flyers, dubbed the complex the "Stonehenge of the North" and slammed North Yorkshire County Council for its treatment of the area when he came to the area to film in 2004. One of Britain's most eminent archaeologists, Richard Bradley recently said "This (the ritual landscape of Thornborough Henges) contains archaeology essential to our understanding of the site and provides a visual context that is becoming increasingly important". TV Archaeologist Francis Prior has called them "a (prehistoric) landscape comparable to Salisbury plain". Popular archaeologist and henge expert Aubrey Burl recently made the following comments regarding Thornborough: 1. Prehistoric henges are the earthen equivalents of stone circles, many of them constructed five thousand years ago in the Late Neolithic period. They are the contemporaries of Stonehenge and Avebury. Amongst these great monuments the Thornborough sites are pre-eminent. 2. There are three of them in a straight line. Such multiple settings are very rare. Amongst stone circles there are only ruinous examples such as the Hurlers on Bodmin Moor. For henges there are only the Priddy rings in the Mendips and they are ploughed down. 3. Quite differently, the Thornborough henges are well preserved. The majority of their counterparts have been levelled by agriculture so that Thornborough becomes doubly important as a complex that can be seen and appreciated. 4. That they were considered important by their builders and the assemblies that gathered there at particular times of the year is the fact that their banks were coated with gypsum to make them gleamingly white and conspicuous. 5. What is not often realised is that these henges did not exist in isolation. They were raised in a landscape already old with earlier monuments, burial mounds, an enigmatic cursus, and they preceded the raising of later round barrows in their vicinity. 6. Prehistoric people were more aware of their physical world than we are. The three henges were laid out to conform with the lie of the land, the ranges of hills, the rivers Ure and Swale. Even the Romans followed the contours with their roads. 7. To isolate these magnificent monuments, leaving them surrounded by water would be akin to dropping Stonehenge into the River Avon. Too many vital links with prehistory and the men and women who were our forebears have already been destroyed or mutilated beyond recovery. There is one other Thornborough "expert" worthy of mention, Tarmac's archaeolgist and ex-North Yorkshire County Archaeologist Mike Griffiths. He has spent more than 10 years excavating at Thornborough in advance of quarry workings and one would expect his recently launched website to proudly proclaim the importance of the archaeology he has found. Yet his site appears to concentrate on the poor state of archaeology and it's vulnerability to ploughing. Little mention is made of the "largest collection of Neolithic features found in the North of England", presumably because most of this was more than a metre deep and well below the plough line. Concentrating on the lesser archaeology which is shallower and therefore liable to plough damage is an understandable bias from the archaeological consultant in charge of overseeing the quarrying operations at Nosterfield Quarry.