NORTH Yorkshire is littered with legends of great serpents, dragons and worms - none more gruesome than that of the Sexhow Worm.

This fearsome serpent, so the story goes, had a poisoned tongue, breathed fire and smoke, and had teeth as large as the prongs of a pitchfork. It had its lair in Whorby Hill, on the western edge of the North York Moors near Swainby, from where it plagued the locals with demands for food, drink and slaves.

Many brave knights died while trying to kill the huge beast, the legend goes - until one day, a local hero named Peter took on the worm while wearing a suit of armour covered with razor blades. As the serpent wrapped itself around him it was sliced to pieces - and one-by-one Peter's dog carried bits of the serpent away and disposed of them.

Sadly, despite Peter's heroism, the story doesn't have a happy ending. As Peter celebrated, his dog licked his face. On its tongue was some of the dragon's poison - and Peter instantly fell down dead.

This might seem an odd story to include in a book with the title North Yorkshire: Strange But True, since while it's clearly strange, it most certainly isn't true.

But what is interesting about this and other North Yorkshire legends involving worms, dragons and serpents, according to the book's author Robert Woodhouse, is the basis of truth that underlies them.

There are a number of theories about where North Yorkshire's worm legends come from - but Robert has his own favourite. "Accepting that these tales have been embellished and exaggerated down the centuries, how do we account for the frequency and persistence of these unlikely sagas?" he writes.

"The most likely link is with Viking raiders who penetrated northern parts in the pre-Norman period, sailing their longships into river estuaries before manhandling them into strategic locations.

"The subjugation of native people and demands for slaves or supplies of food and drink under the threatening presence of the dragonhead prow of their vessels probably gave rise to these monster legends."

Details of various North Yorkshire serpent legends are to be found in North Yorkshire: Strange But True. Robert's remit in writing the book, however, went further than simply unearthing the truth behind the region's monster myths.

Alongside the giants, dragons and occasional appearances even of the devil himself, the reader of this slim book is taken on a guided tour of North Yorkshire's strange and varied past, from eccentric personalities to grand follies, man-made puzzles fashioned in stone and turf to Ravenscar, the North Yorkshire coastal resort that never was.

In a chapter entitled Hills, Horses and Holes in the Ground, Robert deals with two of the region's most beloved landmarks, one man-made, the other not.

It is hardly surprising that a county with such a strong tradition of field sports should display a hillside representation of a white horse, Robert writes. The Kilburn White Horse was first proposed in the early 19th century, with the White Horse of Uffington in Berkshire acting as its inspiration.

"But the work of carving out the huge outline and spreading lime across the surface was completed in the early days of 1857 by John Hodgson, the village schoolmaster, and up to 33 local menfolk." The addition of a rider, as every local knows, was a much more recent event.

When it comes to holes in the ground, North Yorkshire has a beauty. Local folklore suggests that the Hole of Horcum, the beautiful natural amphitheatre next to the A169 between Pickering and Whitby, was formed either by the giant Wade, or else by the devil himself as a punchbowl. "But the truth is," Robert notes, "that it has been shaped by the long-term erosive effects of moorland springs."

North Yorkshire: Strange But True is also good on local superstitions. The fire that permanently flickers in the hearth of the Saltersgate Inn near the Hole of Horcum on the North York moors is one.

Robert gives two versions of the old tale. In the first, the story goes that a man was killed in a fight between smugglers and excise officers and buried under the hearth - and the fire has been kept burning ever since to stop his ghost escaping.

If you don't like that version, try this one: an old hermit who lived in the Hole of Horcum in the 18th century told the Saltersgate's then landlord that if the fire ever went out, the pub would be destroyed.

The Saltersgate Inn isn't the only North Yorkshire pub said to have a fire that never goes out - the Chequers Inn near Osmotherley and Huck-aback Farm, at Castleton, are also said to have fires that have smouldered for year after year.

There is an unpleasant story associated with the Busby Stoop Inn at Sandhutton near Thirsk. One day in the early 18th century, Tom Busby attacked his father-in-law Daniel Auty with a hammer and beat him to death in an argument over money.

It was the custom then to hang a convicted man on the spot where he committed the crime, and then display the corpse on a gibbet beside the public highway. Busby's body was left to rot on the gallows close to the crossroads near the inn.

"And not only is his ghost said to haunt the premises but he is also said to have placed a curse on his chair inside the hostelry," Robert writes. "Anyone sitting in the simple wooden seat would be cursed by the ghost to die within weeks.

"Down the years the sombre forecast has come true - with a number of sudden and unexpected deaths after a victim has sat in the chair. Now the chair has been moved from the inn to Thirsk Museum, where it is tied high up on the wall for safety's sake!"

There is an altogether less gruesome superstition associated with Whitby's Upper Harbour where every year an ancient ceremony is performed. On the day before Ascension Day bundles of stakes and branches are carried to the harbour side before 9am and a "penny hedge" built which by tradition has to survive three tides.

Even this harmless tradition may have gruesome origins, however. "The custom is said to have originated as an act of penance imposed on three hunters by the abbot of Whitby in 1159," writes Robert. "The wrongdoers were chasing a boar, which took refuge in a hermit's cave, and during the ensuing melee the hermit suffered fatal injuries."

Either that, he says, or the tradition of the penny hedge may be derived from an early fish trap. You pays your money and you takes your choice.

Pristine pony... the legendary White Horse of Kilburn has been kept gleaming by regular makeovers down the years including...

North Yorkshire: Strange But True by Robert Woodhouse is published by Sutton, price £9.99

Updated: 10:55 Monday, July 14, 2003