With great glee, two friends in London have sent me a new guidebook. It lists five reasons why nobody should visit the Fens - which, they have always maintained, is a primitive land without any creature comforts. And here they ve found proof that they re

With great glee, two friends in London have sent me a new guidebook. It lists five reasons why nobody should visit the Fens - which, they have always maintained, is a primitive land without any creature comforts.

And here they've found proof that they're right to refuse to travel north of Hampstead.

This guidebook's first two reasons for not visiting "one of the bleakest landscapes in the British Isles" are that it smells and that the air is poisonous. Then there's a danger of catching malaria - and the fourth reason is the local population.

It's obviously not the sort of book that will please Fen tourism - even if the obnoxious smells it mentions are not actually the stink of the Nestle Purina pet food and McCain chips. For, to be honest, this is not a guide to present-day Britain but a description of the island as it was 1,500 years ago. It's called AD 500 and it's by Simon Young.

He imagines the dangers a traveller would face as he toured ancient Britain. Fenland, he fairly accurately reports, was then a land of "stinking mud". Secondly, the so-called poisonous air was famous because it was thought to be responsible for the hallucinogenic mould that grew on the local bread: mould that we now call LSD. And indeed there is ample evidence that weird St Guthlac (who lived the life of a hermit in Crowland) was permanently "high" simply because he ate stale rye bread.

Simon Young's third reason is fair. Malaria was indeed common in these swamp lands in the summer months. As for his fourth reason - yes, the local inhabitants were indeed hostile to the few travellers who ventured into the area. So nothing's changed there, then. Except that our ancestors were themselves unwelcome economic migrants from Saxony, which is why they were called Saxons.

This means that anyone who now claims to be a true Fenlander is descended from an illegal German immigrant.

But what of the fifth reason? That danger was caused by the "thrys" or Fen goblins. They lived underwater. They loved the taste of human blood and would attack humans in foggy weather.

No-one's proved they are extinct. I'm sure the editor of this paper will pay handsomely for the first photo of a live specimen.