IAN COLLINS Brown signs litter the East Anglian countryside - pointing us to Scenic Routes here and all manner of single-site attractions there and everywhere. Far better to embark on a voyage of discovery, with all the excitement and effort that genuine exploration entails.

IAN COLLINS

Brown signs litter the East Anglian countryside - pointing us to Scenic Routes here and all manner of single-site attractions there and everywhere. Far better to embark on a voyage of discovery, with all the excitement and effort that genuine exploration entails.

Just inland from the north Norfolk coast, and most specifically between Stiffkey and Wells, the rolling countryside hides a remarkable ancient treasure. What a treat to discover it for the first time or else, on a summer evening, to take a picnic and a close friend who isn't in on the secret.

From Warham take the sharply rising and falling lane towards Wighton but, once over a bridge, squeeze the car on to the righthand verge by a field gate and track. A police notice about thieves preying on unlocked cars still gives no clue to what is really valuable here.

Walk along the track for 50 metres or so and avert your eyes from an information board which, though very useful at the end of the visit, detracts from the romantic mystery of what awaits, through a gate and in a large field.

Since I'm about to spill the beans myself, you'll just have to take the picnic and the uninformed friend for maximum impact.

Ahead on a tract of undisturbed chalk grassland, a wonder all in itself, are ancient earthworks comprising two great rings, now pierced, and a couple of immense ditches.

On the plain of the central enclosure there is an aged holm oak, like some natural altar, and the whole site tips down to where it touches a bend in the much-reduced River Stiffkey. The view over hedged and cattle-dotted meadows, spiked with trees and Wighton and Warham church towers, is just sublime.

When the evening mist is curling after a hot summer's day, or a sea fret is coming in, the romantic imagination will simply unfurl. So beware: that companion better be a close one.

We're in what is known locally as the Danish Camp, suggesting a Viking settlement before the sea receded and Stiffkey dwindled beyond the reach of most small craft, let along longships.

Possibly raiding norsemen did make an encampment here, but they would have been camping amid far older ruins. The word Danish is habitually attached to forts, battlefields and burial mounds to salute an archetypal enemy.

In fact, this is the best-preserved Iron Age fort in East Anglia - one of four such sites in north-west Norfolk (along with Holkham, South Creake and Narborough), also linking to a larger enclosure at Thetford and to the jewelling centre at Snettisham.

Pottery fragments found on Warham Camp date from 200BC to the first century AD - making this an Iceni settlement which, in all probability, was annihilated or abandoned after the defeat of Boudica's revolt against Rome in AD61.

In their current state, the broken rings suggest the outline of two monumental buried torcs - an impossible tribute to the skills of the Celtic goldsmiths of Snettisham.

But history has snapped the original circles. We approach via an entrance cut in the 1800s and look down to what is almost certainly another break wrought by changes to the river course in the 1700s.

These massive ramparts were constructed from chalk to enclose an area of around 1.5 hectares. Excavations in 1914 and 1959 revealed that 2,000 years ago the ditches were two metres deeper than they are today. They also found the remains of a wooden palisade and walkway on top of the inner bank.

The central area has yet to be fully examined by archaeologists, so its precise purpose remains unclear - a fortress for the Iceni social elite (maybe even for Boudica herself), a market cum refuge in times of conflict, or a religious and ceremonial centre? Maybe any or all of the above.

When I last visited, my thoughts raced across more than two millenniums to return to a present moment drenched in larksong.

Beneath the tongues of common blue, brown argus and painted lady butterflies there flowered pyramid orchids, common (now uncommon) rock roses and wild thyme. I'd lately missed the cowslips - and the cows that watercolourist Gerard Stamp noted in his 1991 tribute to John Sell Cotman, an image illustrated here.

This is a place of magic. And to keep the spell alive visitors, save for artists, must leave no trace that we were ever here.