My editor mentioned a book in his comments on one of the chapters of my new book (to be published next year) which I followed up greedily, as I knew the work of Robert Macfarlane. His book Underland: A Deep Time Journey indeed had important resonances for my own work and I encourage you to read him if you haven't done so already.

In the meantime, here is a 2007 interview with him on his book The Wild Places in which we fondly remember our common and dearly missed friend the writer and adventurer Roger Deakin.

Ramona Koval: Robert MacFarlane is the author of a new book called The Wild Places, a travelogue exploring the histories and landscapes of the wild in Britain and Ireland. His first book Mountains of the Mind: A History of a Fascination took readers on a spiritual journey to the world's highest peaks, and it won him the Guardian First Book Award, the Sunday Times Young Writer of the Year Award, and a Somerset Maugham Award, and it was filmed by the BBC.

He now teaches at Cambridge and writes on literature, travel and the environment for the Guardian and the TLS, amongst other publications. But back to the new book, which takes us on journeys that he names 'Beechwood', 'Moor', 'Forest', 'Cape' and 'Summit', amongst others. On an intellectual and physical journey, guided by monks, questers, scientists, philosophers, poets and artists, The Wild Places explores our changing ideas of the wild. From the cliffs of Cape Wrath to the moors of Rannoch and the Pennines,

Robert MacFarlane's journeys provide the backdrop for the stories of people and cultures, past and present. Some of these journeys he takes alone and some he takes in the company of others, including his friend the late Roger Deakin, himself a writer of wilderness and a very dear friend of mine too.

Robert MacFarlane joins us this morning from China where he's in a studio in Beijing. Robert MacFarlane, welcome to The Book Show.

Robert MacFarlane: Thank you very much.

Ramona Koval: Robert, why did you believe that obituaries for the wild in Britain and Ireland were premature or even dangerous?

Robert MacFarlane: They're dangerous because if we think the wild is gone then there will be no attempt to save what actually remains, what you could think of as relics, or you could think of as jewels alternatively, these wonderful spaces that I was convinced did still exist. The wild is under threat around the world and Britain in a sense is a kind of laboratory for what happens when it's under threat and what you lose when you lose it, so I wanted to go out and test the truth of these obituaries that I'd read.

Ramona Koval: Because, coming from Australia, whenever I fly into England and then I look down and I see everything seems to be apportioned and named and owned, and I think of where I come from and I think, yes, where would there be wild places in this little island.

Robert MacFarlane: I guess that's what I began with, was a worry that it was going that way, it was enclosed and land ownership is so tight and historicised in our country. But I went out and went looking and found places that still retained the power to thrill and to awe and to inspire a kind of wonder and a beauty. There's a question of whether wildness is a function of scale. Your country, the country I'm speaking to now, and the country I'm speaking from, in fact, China, these countries possess wildness on a fabulous scale, and Britain doesn't. It has big moors and it has 7,000 miles of storm-crashed coast but it doesn't possess deserts you can lose yourself in or kill yourself in. But it does have places where you kind of cross borders into other worlds. When you go up into the Cairngorm Mountains you leave civilisation and you find yourself in the Arctic really with Arctic flora and fauna and Arctic conditions. I became interested in those moments where you cross from one space into another, when you step into a forest, and you can lose yourself in a small forest, you don't necessarily need to be able to walk for a day without leaving the cover of trees.

Ramona Koval: Why do you think wild places are, in your view, places for deep dreaming?

Robert MacFarlane: Well, I'm interested in how thought shapes place, that's to say how the ways we imagine landscapes determine the ways we behave towards them. But I'm also more interested in how place shapes thought, and that's a difficult thing to think about and to talk about, how being in a place where you can see for 100 miles might leave a reverberation in your mind and the way you think, or how stepping into a forest or a jungle or to the reaching mountain plateau might affect you in ways that are kind of inscrutable to you. One of the ways these wild places affect me at least, and many of the people I talk to and read about, was a kind of thrill or fibrillation to the imagination that left it kind of susceptible to dreaming and to a kind of visionariness, I suppose. And I keep coming across poets and writers and artists, and even people who lived on the land, for whom contact with the land was a kind of mysticism, if that makes sense.

Ramona Koval: It certainly does make sense. Mysticism, of course, is something that people practise in the wild, and you've found a few places where traditionally monks have gone to somehow be at the end of the earth in some way, to try and connect with something, some other thing. Tell me about that.

Robert MacFarlane: There was this extraordinary kind of Celtic Christian retreat culture which began in the 5th century and pushed forwards from there, and these monks basically went west looking for the edge of the earth, looking for a place that wasn't named. They went out to the islands and the coasts and the forests of the Atlantic seaboard in what we now call the British Isles and founded monasteries and raised crosses to their gods. They went to these places because they were kind of abbreviations of the eternal, I suppose, you could look west and look out over the Atlantic and see eternity, just see endlessness. I find these places very, very moving still. They're compromised now, of course, but people are still drawn to them in the same way, drawn to the margins.

Ramona Koval: Let's talk about maps. You travel with grid maps throughout your journeys but you say that we shouldn't forget story maps for they exemplify a largely lost way of proceeding within a landscape. Do you see your writing about nature about story mapping?

Robert MacFarlane: Yes, I guess so. This book is a kind of chain of stories, a chain of dreams, a chain in which one is connected to the other, and that's how the book put itself together; one story, one anecdote, one tip-off would lead to another. That was the logic I was following was the logic of narrative, in a way, and I became... Australia, of course, has a very deep and complicated tradition of storytelling about its landscape, but the same has happened in Britain in the past, and I became interested in obsessives, in people who told their way round landscapes and navigated by hunch and by correspondence rather than necessarily by the logic of A to B, the logic of transit.

Ramona Koval: What kind of people?

Robert MacFarlane: I met a man called Vaughn Cornish, I met in the sense of met his books, who became obsessed with the idea that the universe was founded on the form of the wave, the physical form of the wave, and he founded a science at the beginning of the 20th century which he called kymatology, and he saw the wave in deserts, in snow, and of course in water. He travelled through the Middle East, Australia, and all Jamaica, West Indies, Northern America, and all around Britain, and kind of mapping in a very fastidious and fascinating way the behaviour of sand and snow and water and wind, and always finding the wave in these places. So here we have a man who is navigating kind of by echo and intuition and a kind of mysticism, but he's also a fierce scientist. I met obsessives as I travelled, people who followed birds and used their logic of motion to navigate themselves, people who wanted to get away from the motorway and the hotel.

Ramona Koval: What about this man WH Murray whose essays you had read? I hadn't heard about him. Tell me about why he was so important to you.

Robert MacFarlane: He's a wonderful writer. I'm sure there would be an equivalent of him in Australia. He was a Scottish mountaineer, explorer, who became obsessed with the glens and high places, the wild places of Scotland in the years before the Second World War. He spent five or six years night-climbing and naked swimming in wonderful remote lakes and lochs and tarns, and then he went to war to fight in the desert in Africa and was imprisoned after Tobruk. He wrote his first book while incarcerated in a variety of prison camps. He wrote it under extreme conditions, first on toilet paper and then when the toilet paper ran out his mother sent him out the complete works of Shakespeare which apparently made better toilet paper then the standard issue so he bartered that for more blank paper. He wrote this kind of dream work, I call it. He remembered Scotland from the times he'd been there and it was his great consolation and salvation through that time as his body began to fall apart under the pressures of confinement. It's just an account of the adventures he had. I remember reading it for the first time and thinking you can have adventures in Scotland or in Britain which in their ways are as remarkable as getting to the Arctic or getting to the Australian desert would be for me. And that kind of excitement of the local, of the near-at-hand, of this world that's just beyond your glance or your gaze if you only know how to look for it. Murray wrote inspiringly about that.

Ramona Koval: You went on your journeys sometimes alone but sometimes with friends, and sometimes with our friend Roger, a wild man in love with the wilderness, Roger Deakin, who was your friend and my friend. Tell me about how Roger and you travelled together.

Robert MacFarlane: For those who didn't know Roger (and Roger died just over year ago now, far too early), he was a man of extraordinary passion and enthusiasm. He swam and climbed his way... well, swam and walked his way around England in a way that I think nobody else ever has, but he also came out to Australia and travelled with you, I know, Ramona. I travelled with him... he really taught me to see England. I wasn't that interested in England four years ago, I always went to Scotland or to the mountains elsewhere when I wanted my wild hit. And I wasn't really sure where the wildness did survive in England. But travelling with Roger, he was kind of this big kid really, this wonderful, knowledgeable, digressive child in the best sense of that word. We went to Dorset into the Holloways which is a southern English county on the sandstone, and there are these ancient roadways carved 20, 30 feet down into the sandstone there which are kind of tiny gorges really in the middle of all this farmland. They are wonderful little wild ravines where nobody can get down into them except venturesome pedestrians like Roger. Roger and I went on an adventure following this kind of subterranean labyrinth of the wild around Dorset, keeping out of sight. And we went to the Burren in the west of Ireland. We were due to come out to Australia to speak at the Watermark Festival, your great festival of nature writing and landscape writing, or the writing of place is maybe a better word for it. So yes, everything he did was wild in the sense of improvised and self-willed and unconventional. He was a great teacher, and in a way the book is a kind of tribute to a deep friendship but also a friendship of learning for me.

Ramona Koval: I remember him telling me that he was going to go camping with you to... it sounded to me like you were going to go into a hedgerow and have a little cubby together, and because he was following an old book that he wanted to see whether it was possible for people to hide in a cubby of a hedgerow and not be found. Tell me about that.

Robert MacFarlane: That's pretty much it. What's a cubby? Is a cubby like a den?

Ramona Koval: Yes, like a little den, like kids, they have a cubbyhouse in a tree or in a secret spot so adults wouldn't know that they were there. And they have their food and they have little toys and stuff like that in there, it's a little secret spot.

Robert MacFarlane: That's it, a little secret spot. That's exactly it. I was on the lookout for secret spots and nobody knew secret spots in England like Roger who could find them underneath a bridge on a river when he was canoeing down it, and he would stop and talk about how the light plays differently and the sound is different in such a place. Everyone will know that kind of echoey under-bridge world, but for Roger that was somewhere to spend half a day. So we made our cubby in these deep hedged Holloways and saw if we could stay out of sight and out of detection, and yes we were following the trail of Geoffrey Household's hero in his novel Rogue Male from 1939. Roger was a rogue male in the best sense of those words.

Ramona Koval: Yes, he was always interested in wild men, he said, like himself. Like the time and wildness, you say friendship with Roger didn't follow the normal laws of time. What do you mean?

Robert MacFarlane: Well, I only knew him for four years but I felt like I'd known him my whole life and that I will continue to know him my whole life. So in a way there's a kind of deep time to that friendship too. I've never experienced a friend or a man who could bend time and stretch it in those ways. That was partly because he filled every second with story and vigour and passion and unexpectedness. You could never take a road or a path with Roger without him wanting to strike left and then right, and he came at the world diagonally and never straight, he saw it slant. And so the time that one spent with him was unforgettable and occupies much more of one's sense and memory than normal time, so yes, another kind of wildness embodied in him. When I began the book four years ago I knew it was going to be a book about loss, the loss of the wild, in a way, but I didn't know that it was going to be a book about the loss of Roger and his wonderful wildness. In a way he came to embody some of the values of the wild that I'd found in landscape only before.

Ramona Koval: As I said, sometimes you walked with Roger and sometimes you walked with your father and other people, but sometimes you walked by yourself. Tell me about this walking at night.

Robert MacFarlane: Well, you've done it, I know you've...and I'm sure many Australians have been in the desert at night. It's a fabulous experience, right? To be under a trillion stars, out from the sodium umbrella, the glow of the city.

Ramona Koval: I'm not sure that I would walk at night in the way that you're suggesting because you don't know what you're going to walk on or if something is going to dip. I mean, I'm not a wild man remember.

Robert MacFarlane: I wanted to travel wildly as well as widely, and one of the ways to come to know the landscape differently was to travel at night. Two things I'll never forget; one was swimming at night in phosphorescence off the north Wales coast, which really did feel like I'd stumbled into a scene from TH White or... I was about to say Harry Potter but I won't... where every movement you make provokes colour, lilac and turquoise and silver. And to find that in the Irish Sea, as those who know Britain, it's not the kind of miracle you expect to find off the Welsh coast. But the other was walking at night in winter mountains in the Lake District in Cumbria. If you're a night walker, you want light so, as you say, you don't fall or slip, and snow with its reflective qualities and ice gives you the maximum lustre, as it were. So it was a clear night and there was hard snow and hard ice, and I climbed in the day and camped high and then at night once the bad weather had subsided and the Moon had come out I walked this ridge. And it really was like stepping onto another planet or another world, or at least into Antarctica. Deep shadows in the valleys, white light reflected up and onto me, and everything glistening in this strange monochrome way of the night world, and stars falling far above me, and it was... yes, this was unforgettable, and I night-walked wherever I could really.

Ramona Koval: Robert, I spoke then about my disinclination to walk at night given I was a bit afraid, but fear and wildness came together for you in a moment on Ben Hope. I want you to talk about that because it was unexpected for me as a reader. It sounds like it was pretty unexpected for you as a person who was there and a writer.

Robert MacFarlane: Right. Ben Hope is the most northerly of Britain's Munros, so it's our big boreal mountain, the Munros are the mountains over 3,000 feet which I know sounds tiny, but given our northerly latitude they can be pretty extreme places. I wanted to spend a long winter night on Hope summit as a kind of northerly point of my journeys, and from there I would turn and come south. So I set off late in the afternoon on a cold day, got up to the summit, and I was expecting, I guess, an epiphany, I was expecting some kind of great exhilarating northerly night, and instead I found myself terrified... not terrified but deeply disturbed by this kind of... I mean, I was on a summit, frost shattered, absolutely inhospitable, with which there could be almost no communion, I could see no light, north of me was the Pentland Firth, north of that still the ice of the Arctic. There was nothing, nothing to get purchase on. And I wanted to leave by the time... I couldn't sleep, it was too cold to sleep, and so I spent the night pacing this summit. It was too dark to get down safely. And yes, it was very salutary. I was expecting, as I say, a kind of reward and instead I found the land had absolutely no interest in my presence there. And this was great, this was in a way a northerly point. The Inuit have this word 'ilira' which means the feeling of fear and awe that fierce landscape can provoke in a person. It's a lovely word and it's kind of a version of our word 'sublime' but I prefer this word, and that's what I felt up there.

Ramona Koval: But it's more than sublime though, it's deeply... it's just like everything is shaking you and you have to escape it or something.

Robert MacFarlane: It is indifference. It wasn't that the landscape wanted me off, it wasn't that it was trying to evict me, it was just it was going about its business and its business was strong wind, cold snow showers, little moonlight and ice forming and cracking in the pools around me. That was the land's process and I was incidental to that, but it was extremely uncomfortable to be there. So it was an indifference, yes, powerful.

Ramona Koval: And did that temper your romance for the wild?

Robert MacFarlane: Yes, it reminded me; don't idealise. I am a romantic and I'm fascinated by romantics, and I think a well controlled and a well channelled kind of landscape romanticism is a powerful force for good in all sorts of ways. But yes, a reminder, as I say, salutary.

Ramona Koval: You have a line there that I've written down: 'The discretion of trees and their patience are both overwhelming and affecting.' 'The discretion of trees'? Tell me about it.

Robert MacFarlane: Well, they keep their counsel, they speak their own languages, they communicate with one another chemically, and there's a phenomenon called crown shyness which is where trees will, as it were, respect each other's light space, and this is what makes it reasonably difficult to, as I tried at various times, to traverse a wood or forest at treetop level. I did a lot of tree climbing.

Ramona Koval: And tree walking-across.

Robert MacFarlane: I tried to traverse but it's actually very hard because trees generally, at least in British woods, respect each other's space reasonably carefully, it's not quite like a jungle. And because I don't have brachiated arms like a gibbon, so I can't swing...

Ramona Koval: Yes, I remember meeting you once and I thought, he doesn't have brachiated arms like a gibbon.

Robert MacFarlane: It's often how I'm introduced. But Roger was very keen that I try a treetop traverse.

Ramona Koval: And have you seen Roger traversing treetops?

Robert MacFarlane: No, he wanted me to be the experimental monkey. Yes, tree climbing became another wonderful... you learn the habits of different trees, their amenability to being climbed; the chestnut with its great canopy but wide and difficult first main trunk. But yes, the discretion and the patience. An oak tree can famously take 300 years to grow and 300 years to die, and this is an abbreviated version of rock time.

Ramona Koval: I was also very impressed with the way you express yourself about the wild. I've written down a phrase: 'Water, plump and gleaming'. I don't think I've ever heard water described like that.

Robert MacFarlane: Thank you. But the surface tension of water... a droplet is plump, a droplet sitting on a surface is plump, and I think I was writing there about where tide races meet, you get this up-welling, this kind of gouting of currents that rise vertically, and so the whole surface of the sea feels like it's being pressurised from below, and the meniscus inverts and you get this feeling of a kind of plump, flesh-like surface that could give at any minute. So, plump and gleaming, yes, but also quite alarming as well with those currents working their strong force, but invisibly.

Ramona Koval: Perhaps you could read that little bit from the first part of the book called 'Island'.

Robert MacFarlane: Yes, I will.[reading from The island's name is... to ...history to eternity.]

Ramona Koval: Beautiful. Robert MacFarlane, what are you doing in China?

Robert MacFarlane: I'm out here writing some essays for the BBC about China and its relationship with its nature and its wildness, and I'm following my wife who is a writer about China, a sinologist, who is writing a book on Chinese nationalism. So I'm out there on sabbatical, giving some lectures and writing some essays.

Ramona Koval: And what are you finding about the Chinese view of wildness?

Robert MacFarlane: Venerable, complicated, and there is relatively little relationship between a kind of elite imagining of nature with its Taoist world view which many of us would be familiar with which venerates nature, and the actual massive industrialising of the Chinese landscape which has been going on for 4,000 years. I'm in Beijing and it's a birdless city, which was one of the first things I noticed. I arrived in migration time, September, and there were almost no birds in the sky. And the pollution here is sometimes so bad that you can't see for more than half a mile and it rates in the 200s on the air pollution index. In England, if it gets above 100 in London they issue a public health warning. So there is nature here in this city but it's much harder to find, and it's odd not having birds glimpsed out of the corner of the eye in the sky.

Ramona Koval: Does it make you sad, Robert?

Robert MacFarlane: Sure, but it may be a function of my blindness, I may be looking in the wrong places. I'm going to join (Roger's influence again here)... there's a so-called 'polar bears club', old Chinese gentlemen who break the ice on the park lakes here at Houhai and Qinghai when the winter comes, and it comes hard here. They chop out a kind of bathing area from the ice, and I'm hoping to get to know these people, join their culture, their group, and when the ice finally comes, December, swim with them. But we shall see. Apparently I need to prove... that my chi needs realigning.

Ramona Koval: How are you going to do that?

Robert MacFarlane: I think I need to meet with them and swim with them regularly over the coming weeks and months before the real cold comes. They have, as far as I can tell, fabulously complex theories that I think Roger would have approved of about the restorative powers of extremely cold water.

Ramona Koval: He would have too, yes. It was lovely to read your book The Wild Places which is published by Granta, and it was beautiful to be reminded of our friend Roger Deakin and his lovely madnesses and beautiful clear views about nature. Robert MacFarlane, thank you so much for being on The Book Show.

Robert MacFarlane: Thanks Ramona. Mountains of the Mind, Robert MacFarlane's first book, won the Guardian First Book Award and the Sunday Times Young Writer of the Year Award. He is a Fellow of Emmanuel College, Cambridge. He tweets as @RobGMacfarlane