People were thicker on the ground in much of rural Northumberland than is the case today. Archaeological research shows that farming was also more intensive and widespread than now.

Cultivation around 3,500 years ago was taking place on hills at heights of up to 1,400ft.

"This implies a large population largely devoted to farming," said Newcastle University archaeologist Clive Waddington.

"Trying to imagine the barren Cheviot hillsides of today littered with farms and fields takes a great leap of imagination, but that indeed was the case.

"The intensification of farming and settlement was far greater than today and with no mechanisation and hand-digging many more people were needed to work the land,

"The population of many rural areas was substantially greater.

"It is astonishing to think that many of the valleys, particularly in the uplands, were much more heavily populated in the late Bronze Age and Iron Age than they are today."

Clive said that places such as the Breamish Valley in the Cheviots had Bronze and Iron Age populations anywhere between 10 and 20 times greater than now.

"If you extend that across the county you are looking at a much bigger population," he said.

Evidence in the uplands of the prehistoric farmers' round houses and fields has survived because later agriculture never again reached such altitudes.

Clive, with Newcastle University geographer Dave Passmore, has written a book which gathers together research and the evidence from excavations to plot the development of human society in Northumberland from 10,000 years ago to the coming of the Romans.

Ancient Northumberland, published by CountryStore, was launched at the weekend by Meet the Ancestors TV archaeologist Julian Richards. "The prehistoric landscapes of Northumberland compare with the best anywhere in Europe," said Clive.

"Northumberland is an extraordinary place, a land of stunning scenery and world famous archaeological heritage.

"Although best known for Hadrian's Wall and its many castles, the county is also home to the finest examples of prehistoric rock art in England, the greatest concentration of henge monuments, the largest number of hillforts and defended sites, and one of the best preserved Bronze Age upland landscapes in Europe.

"The book is dedicated to sharing what is known about the early inhabitants of this region - their way of life, their homes and monuments, and their relationship with the land."

Julian said: "The prehistoric archaeology of Northumberland has been a well-kept secret for too long."

Discovery led to hut reconstruction

The book launch event took place at the Maelmin heritage trail at Milfield, near Wooler, where prehistoric features have been re-created, based on information gleaned by archaeologists.

One of the reconstructions is of a hut where the outline emerged from excavations in 2000 and 2002 at Howick on the Northumberland coast, dating from almost 10,000 years ago.

The find pushed back evidence of human occupation of Northumberland by 2,000 years, although a harpoon made from an antler and found at Whitburn in South Tyneside is thought to be even earlier.

The hut measured 20ft in diameter and would have accommodated a family who made use of the food offered by the seashore, including seals, fish, shellfish and seaweed, and the products of the land such as deer and wild pig, birds, nuts, berries and leafy plants. More than 13,000 pieces of flint were found in the hut from the making of stone tools.

Another discovery was red ochre. This can be used as a sun block and to keep insects off the skin.

It also has antiseptic qualities and helps to staunch bleeding, and can be used as body paint.

"Once built, the hut was found to be spacious, warm and a suitable size for six to eight people," said Clive.

Unearthing the past

Around 6,000 years ago pottery began to be made and the production of food intensified.

An excavation at Bolam Lake revealed the remains of a fenceline and cooking areas around what would have been a timber-framed structure, possibly roofed with hides and which could have been put up in a day by mobile herdspeople.

The first burial mounds appeared and also henges, or circular earthwork monuments which are believed to have been ceremonial centres. The use of bronze brought a wide range of tools, weapons and ornaments while from the late Bronze Age to the Iron Age, many settlements began to be defended by wooden stockades, with hillforts home to extended farming families. One heated debate is over the purpose of burnt mounds. These involved heating stones in a hearth, placing them in a stone-lined trough and pouring water over them.

This gave off steam. Some archaeologists argue that this involved cooking while others believe the system served as a primitive sauna.

Pagans offer reward in bid to catch vandals

Pagans are clubbing together to offer a reward for information leading to the apprehension of vandals who daubed yellow paint over a 4,500-year-old stone circle, it emerged yesterday.

The Rollright Stones, near Chipping Norton on the Oxfordshire/Warwickshire border, were splattered in an incident which was discovered on Thursday.

Now the Pagan Federation has stepped in, urging its members to pledge cash which they will pay up if a conviction is secured.

The organisation's secretary, Karin Attwood, said she was optimistic the total would top £1,000.

She said: "The feeling of the Pagan community is that they are so outraged, they want to do something about it.

"We have had offers to help with the clear-up and pay for CCTV.

"But this seems to be the most efficient way of dealing with it."

Ms Attwood, who is also a trustee of the Rollright Trust, said that the 100ft diameter circle of stones was more popular with pagans than even Stonehenge because of its connections with witchcraft.

Pagan myth has it that the circle came into existence when a witch spied an invading king and turned him into stone.

There are references in history books to witchcraft being practised there as late as the reign of James I. "In terms of a connection with our ancestors, it's held in very high esteem," she said.

"There have been marriages, birthing ceremonies, ash scatterings there - it's similar to Canterbury Cathedral for us."

There are estimated to be around 250,000 pagans in Britain.

Anyone wishing to make a pledge towards the reward should go to www.paganfed.org, then click on the link to email the secretary.

How the landscape changed

Geographer Dave Passmore has worked on how the landscape of what is now Northumberland has changed over millions of years.

It is believed that Northumberland was covered twice by glacial ice, or Ice Ages, with the last being 18,000 years ago.

When the region became ice-free 15,000 years ago, meltwater torrents cut deep channels in hills and valley sides, which survive today as dry valleys in the high ground of the North Pennines and the Cheviots.

In other areas the waters deposited thick layers of sand and gravel in terraces. At one stage what is now the Northumbrian coast looked out over much lower sea levels and a vast, low-lying tidal plain which formed part of a land bridge connecting eastern England to the north-west European mainland.

This landscape was gradually drowned 6,000 years ago, and at Hauxley and Druridge Bay, peat layers, ancient tree stumps and lagoons lie beneath sand dunes.

By 5,000-7,000 years ago, forest had expanded across most of the county as the climate entered a period of sustained warmth with temperatures 2C-4C higher than today. As people began to domesticate animals and grow crops, deforestation began. "Only the modern conifer plantations of Kielder can begin to provide some impression of the vast expanse of natural forest cover that was once so characteristic of the Northumberland landscape," said Dave.