How we've made the British landscape

Two lines of ancient wooden posts jut out of a glittering pond girdled by rushes. Two swans flirt idly on its surface as moorhens loop over the water. A man in a wax cotton jacket stares thoughtfully across a landscape recreated to resemble what Britain would have looked like 3,500 years ago. If it weren't for the aeroplane contrails in the sky you could well imagine a Bronze Age farmer marching over the horizon, his flock in tow.

The jacketed man wanders up to a circular house. He pats its grassy surface. A ring of timber uprights support its wickerwork wall and a thatched, living canopy. He ventures inside and sits on a wooden bench next to a round hearth, the smell of a burned-out fire still pungent in the air. It's surprisingly warm, and the gentleman in question, with his thick beard and strapping frame, appears blissfully at home.

In many ways, Flag Fen, an archaeological site, and now a tourist attraction, just outside Peterborough is Francis Pryor's home. He is the excavator who first stumbled across the site in 1982 and has led digs here ever since. He's the researcher who trumpets its ancient oaks and metalwork on Channel 4's Time Team. And now he's the author who writes extensively about it, and much more, in his new book, The Making of the British Landscape. The archaeologist hopes the volume will reacquaint a fresh generation with their surroundings, and demonstrate how, since records began, Britons have bent, bashed and whittled the landscape to suit their needs. From the sprawling fields of East Anglia, to the mountains of the Pennines and the waters of the Lake District, humans have had a greater influence on their surroundings than we may think.

The Fens, 400,000 hectares of former marshland south and west of the Wash, are the perfect example of this. On the face of it, they are flat and featureless. But a dynamic story lives beneath this characterless surface. "There's no other region that has been so intriguingly sculpted by mankind, from a large to small scale, from Bronze Age man to the innovations of the Victorians," says Pryor. "I've lived and worked here for decades and made it my home simply because I've become so obsessed by it."

The Fens or "Fenland", has two distinct zones. To the east, there is a wide band of silty marine soils, known as Marshland, in which we find towns such as King's Lynn, Wisbech and Boston. To the west, fringed by dryland towns including Cambridge, Huntingdon and Peterborough, are freshwater peats, or Black Fens.

The landscape is defined by the differences between these two areas. The slightly higher and more stable silts of Marshland required less man-made drainage over the years, but are susceptible to storm damage. The less stable peats of the Black Fens have required deep drainage, and the peaty soil shrank as it dried out.

Flag Fen – a huge ceremonial burial site and barrier between communities – was just the beginning. Here Bronze Age people made a fence of at least 40,000 wooden posts and a huge wooden platform to keep the Fens' marsh waters away from their animals. Despite this, it is clear that little remains of Bronze Age landscapes today. Gone are the droveways – oblong fields used to keep sheep and cattle – to be replaced by the wholesale destruction of hedges that accompanied modern farming. Soay sheep, their devilish horns curled above matted coats, have given way to more modern breeds.

It all fits in with modern archaeologists' concept of the landscape as a palimpsest, a parchment that is scrubbed down and re-used. The Fen Causeway, an ancient Roman road, is still visible at Flag Fen, built on the remains of the original Flag Fen site. Much later came the pumping stations and drainage channels drying out the Fens' bogs and converting them into fertile farmland. Driving around Peterborough you might see the River Nene with its raised, flood-preventing banks, strengthened during the late 19th century. Elsewhere are concrete pill-boxes, the first line of defence against the Luftwaffe in the Second World War, standing silent guard over tiny villages.

So which of these factors has had the biggest influence on the Fens' landscape? Certainly not the Romans, whom Pryor seems to blame for most of the country's ills. "If I were to give the Romans credit for one thing, I would say that they brought us some prosperity," he spits. "And our motorway system mirrors their roads – so we can blame gridlock around the M25 on them."

Here it seems as though drainage has had the most importance. In the 1630s, locals cut drainage channels from the marshland into the rivers, but as the marshland dried out its level fell and it was soon reflooded. Then in the 1820s huge coal-powered steam engines were built, such as Stretham Old Engine, a magnificent brown-brick building that still towers above the River Great Ouse. Today, modern electrical pumps and miles of flood defences keep the elements in check.

In fact, the landscape's low-lying lack of features is the greatest evidence of man's legacy. At points around Peterborough it is possible to see straight to the horizon. Like the reclaimed portions of western Holland, ranks of modern wind turbines tower over fields of sugar beet and wheat.

At Holme Fen, a nature reserve just south of Peterborough, there is a slightly tired-looking, cast-iron green post. When the Victorians began to drain the nearby lake of Whittlesey Mere, the local landowner, William Wells, sank the post into the peat to measure how much the dirt shrank as it dried out. In 1848 the post's top was the same level as the earth. Today, its summit is four metres above ground. It marks the lowest point in Britain, and is the centre piece of what is now a stunning silver-birch wood overlooking a man-made lake.

Necessarily, Pryor's comprehensive book touches on much more than the Fens. The days of ritualised, pagan England, most famously at Stonehenge, are set alongside vivid descriptions of a more practical harnessing of the terrain by our Bronze Age and Iron Age ancestors, with megaliths and barrows – of which there is one at Flag Fen – used as boundary markers. The tome is full of juicy facts: Bronze Age man used forts both for penning in their cattle and pelting Roman legionnaires with stones. Much later in history, he discusses everything from the gardens of stately homes, to the influence of landscape poetry, medieval open-field farming and the modern planning system.

"Digging within the Fens concerns day-to-day human life, and the study of that is what motivates me," he says. "I'm interested in how communities function together, how they shape the world around them, how they provide for their families or follow a profession. I don't want to know what aristocrats had for breakfast; I'll leave that to David Starkey. I'm much more concerned by what their man-servants were eating, cooking, sewing, and how that shaped the world around them. Most of those who lived in the Fens, from Bronze Age times on, were the ordinary people of the day. They tried to get along as best they could – much as we do now."

He is, however, not without concerns. If sea levels rise, he believes the Government would allow the sparsely populated Fens to go under water. He laments the destruction of archaeological sites through modern farming, and the problems that may result from rising food prices and continued urban sprawl. Nowhere will this be felt more than in the Fens, a major source of British food. With its 4,000 farms, the region employs 27,000 people, producing a quarter of the potatoes grown in Britain, and 37 per cent of the vegetables.

If that, then, is a microcosm of man's alteration of the landscape, then Pryor's appreciation of the landscape is an island of honesty equally worthy of protection. He loves everything about England. He sees the changing seasons in terms of "the snowdrops among the gravestones in February, daffodils in April and roses in June". He says he's more optimistic than other researchers, who lament the decline of the British landscape after the Second World War. "We've really got to look after these things for their own sake," he says, bidding farewell with a cheerful wave. "The landscape is our story, as told by us. And as such, we should do everything within our power to cherish it."

'The Making of the British Landscape' is published by Allen Lane (£30). To order a copy for the special price of £27 (free P&P) call Independent Books Direct on 08430 600 030, or visit www.independentbooksdirect.co.uk