The cult of the wild grows ever stronger. Last year saw the publication of Roger Deakin's Wildwood, Jay Griffiths's Wild, Richard Preston's Wild Trees, Simon Barnes's self-helpish How to Be Wild (which one feels ought to be subtitled Graaarrrgghh!) and - I should probably declare at this point - my book, The Wild Places. The film version of Into the Wild, Jon Krakauer's reportage classic, was also released. This year has seen a second wave of wild works of a more

pragmatic kind: including Christopher Somerville's splendid compendium of 500 wild sites and sights in these islands. What's going on? Why have we gone wild for the wild? This recent surge has various parallels in the last century, notably the rural revival of the 1930s and 1940s. You might remember the Batsford Books of those decades, with soothing titles such as The Countryman's England and Knitting Patterns from Nature. They were illustrated with distinctive prints showing bosomy downlands, fruit-slung hedgerows and steam trains chuffing up hill and down dale. The success of the Batsford aesthetic lay in its bucolic calmness - the reassuring visions of order and contentment in an era of world war. This time round, though, we seem hungry for a more chaotic and edgy version of nature: “the wild” instead of “the pastoral”, the feral rather than the rural.

Somerville, in his introductory essay, puts this hunger down to the current mood of ecological apocalypse. Guilty at the environmental consequences of human activity, and angsty about our increasing separation from nature, “we now need the wild as never before” - both as reprimand and blessing. A psychopathology of a kind, then. But not a bad one to be suffering from, it seems to me.

Britain and Ireland's Best Wild Places took Somerville a year to research. And a hard year it must have been - he covered thousands of miles by car, plane, train, bicycle and on foot, in all four seasons, and in many weathers. When he began his journeys, he had a singular sense of the wild in mind, epitomised by “the rugged unpopulated landscapes of the outermost north of Scotland, or the Atlantic outposts of the west of Ireland”. The wild as a function of scale: of uninterrupted sightlines, of storm and ice and sea.

But in the course of his travels, that singular definition shattered and splintered. Wildness “came in a thousand forms”, Somerville realised. Just so. And one of the several virtues of his book is its joyful polytheism. He finds the wild there in West Country sculptures of green men “spewing mouthfuls of leaves”, in “deep pink drifts of valerian” on the Isle of Portland, in the stink of “rotted leaves bubbling from an iridescent pond” in the Forest of Dean, as well as in more expected places like the singing-sand beaches of Eigg, and the “roadless valleys” of County Mayo.

The notion of a guidebook to the wild is a paradox, of course. How do you produce a gazetteer to a force or experience whose defining characteristic is a refusal to be defined. How do you order the unorderable? Well, Somerville has done almost as good a job as is possible. His book is divided up by geographical region (The West Country, Wales, The Highlands and the Isles, and so forth). Within these sections are individual entries on each place, including details of relevant ordnance survey maps, location, access, flora and fauna, and a few hundred words of description. The book is a success of organisation (what a wrestle with data it represents) as well as of observation. Barring the inexplicable absence of an index (a serious skimp in a book of this kind), it has been beautifully produced. Heavy in the hand, extensively illustrated, and with a colour-scheme of leaf-green, field-brown and slate-grey, it's an exemplary piece of book craft.

The best guidebooks - Betjeman and Piper's Shell Guides, say, or Pevsner on architecture - don't prescribe or totalise their destinations, leaving the reader only to traipse round on a pilgrimage of gawping obedience. Instead, they inspire adventure, improvisation and the learning that comes from discovery. Somerville's book is in that valuable tradition. His descriptions of individual places are rife with enticing phrases and gleaned insights. Oldbury Fort in Kent is hidden “under a smother of trees”; he sees the “sorrowing stone women” of Abney Park cemetery in Stoke Newington, who “glimmer whitely inside the clasp of elder bushes”. The northwestern mountain of Suilven in Scotland is a “striated sphinx”. Lesser centaury flowers are “nail-polish-pink”, and on the Isle of Lewis he hears “the sharp tick of pipits”. Reading him, you want to get out, get walking, get looking.

There's humour here, too: in Abney Park cemetery, for instance, Somerville encounters the plinth of Isaac Watts, and notes that the Restoration hymn-writer was responsible for such “splendid and resounding hymns...as When I survey the Wondrous Cross”, and also “some more obscure numbers, including Blest is the Man whose Bowels Move”. Strange indeed. But then what was it the American nature-prophet Henry David Thoreau wrote in 1856? “It is in vain to dream of a wildness distant from ourselves. There is none such. It is the bog in our brain and bowels.”

Britain and Ireland's Best Wild Places by Christopher Somerville
Allen Lane £25 pp544 Buy the book from Books First £22.50 including free delivery

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