Tom Brooks looks out across the Dorset uplands with a countryman\’s assured eye, but also with a frown. Here, near the village of Milborne St Andrew, the latest Ordnance Survey maps show a prehistoric long barrow, or \”chambered tomb\”.

But the monument has long gone – only a slight rise in the field suggests its one-time location. \”You wouldn\’t know there had been one there at all,\” Tom says. \”And along the hedgerow, there\’s supposed to be a tumulus, but it\’s not there either.\”

Near Tom’s childhood home in Devon, the hill camp of Stockland Great Castle is under threat, reduced in size by half over the years by agricultural encroachment. Tom, a retired marketing director, is deeply concerned about such losses because of a remarkable discovery he has made – that our ancestors perfected a kind of Stone Age sat-nav system.

After decades of meticulous research involving countless mathematical computations, based upon the true position of each ancient site relative to all others according to the Ordnance Survey National Grid, Tom believes he has decoded Britain\’s prehistory – proving that our ancestors, far from being barbaric, actually possessed sophisticated engineering and surveying skills.

He has found that, across England and Wales, more than 2,000 prehistoric monuments – long barrows, hill camps, mounds, standing stones and stone circles – dating from 4,000-5,000 years ago, do not stand alone but are integrated geometrically in a vast network based on a system of isosceles triangles (those with two sides of equal length) and equidistance between sites aligned with precision over great distances.

And this – \”one of the world\’s biggest civil engineering undertakings\”, Tom says admiringly – was created more than two millennia before the Greeks were supposed to have discovered such geometry, although many of its sites have been damaged or lost.

Tom’s latest research has been marked by the launch of a small website and the publication of his findings in new book, Prehistoric Geometry in Britain: the Discoveries of Tom Brooks. Such is his dedication to his cause that he has been producing a limited edition of the book by hand.

He reveals that the 5,000-year-old Silbury Hill in Wiltshire was the hub of the network, which he regards as navigational, offering a convincing solution to the mystery of the purpose of the largest man-made mound in Europe, but a challenge to established archaeological thinking.

\”Planning authorities pay scant regard to our prehistoric heritage as do farmers who, in most recent times, still plough flat the long barrow and earth mound that is actually shown as extant on the latest Ordnance Survey sheets,\” said Tom.

\”We must take all our antiquities into enhanced care and apply severe sanctions to the offender. No other country in the world can boast so many jewels from the distant past which, together with the geometric connotation, represents wealth untold.

\”Every such item is a node in the only example of prehistoric geometry to have been unearthed anywhere in the world. Imagine the advantage to the British economy when it is finally recognised overseas that here, at one time in earlier centuries, superior minds were being applied to leave a message across our landscape to be – a positive magnet for tourism.\”

Despite the \”breathtaking scale\” of prehistoric monuments, and the unexplained nature of their construction by supposedly primitive men, the respect of British people today fell very short of what should be expected.

\”My research travels have taken me to key mounds in the geometric layout being hidden in private gardens where permission to review is so often refused, or to modern soulless housing schemes were Tarmac roads and drives completely encircle a treasured but deformed representative of the past.\”

Ruefully, Tom recalls an encounter, nearly 20 years ago, with a pig farmer in the Vale of Pewsey, Wiltshire, who had allowed his animals gradually to destroy a long barrow: \”He threatened me with dire consequences if I approached his land again and I reported him to English heritage who did nothing.\”

Tom, who lives in the Mendip Hills of Somerset with his wife Sue, says antiquities should be \”rescued\” from private ownership and returned to the public whose heritage they represent.

\”Stern measures must be taken against those who today still wilfully destroy and vandalise these unique representations from our veiled and distant past, and that where an ancient unit is known to have existed in recent time, either a permanent labelled marker be installed or a replica feature introduced,\” he said.

It was as a child that Tom\’s fascination with prehistoric Britain began, as he explored hill camps in Devon\’s Blackdown Hills. At 14, he spent three days sketching all he could see through 360 degrees from Hawkesdown Camp above the Axe estuary, and wondering if the landmarks on the skyline were part of some grand scheme.

Then, on his cycling trips, he found that the great camps of Musbury, Blackbury and Sidbury were aligned. To prove the alignment mathematically, he overlaid a grid on a one-inch map – and his life\’s work had begun.

What has driven him? \”I hope to get some recognition for my work, not just personally, but for the geometry I have discovered which indicates we had an intelligence here 5,000 years ago which is way beyond expectation,\” he said.

\”Much of the accurate triangulation with two equal sides would have been surveyed by line of sight from the highest point available. It\’s still possible today to see 25 miles across country but more in prehistoric times with no high-level tree cover nor intervening buildings and a totally unpolluted atmosphere.

\”As the large hill stations were created for permanent living, long barrows for overnight rest or shelter by workforces, and mounds with standing stones as waymark signposts, so would the constructors be joined by families and thus able to help with agriculture and mineral extraction to develop trading across the network.

\”We have been led to believe that long barrows were pagan ritual burial sites, yet with no evidence of formal respectful arrangement, as in the Pyramids. Even today, they make quite comfortable overnight shelters. They are found on isolated high ground, close to major construction work, as at Silbury, Stonehenge and Winklebury Camp, Basingstoke, and without exception are key nodes in the triangulated network.”

Back then, says Tom, Britain was unbroken territory, just rolling, bare countryside with a hostile environment after the Ice Age. To expand from warmer southern climes for a growing population called for a controlled system for planners to know where workforces were heading and navigators to know how to return or cross-connect with others. Trading and social inter-connection would have come later.