Last year, during the height of summer, I stood atop a grassy knoll looking out over a sweep of alien landscape. Set against a gunmetal-grey sky, a rich autumnal carpet was draped over valleys and mountains alike, giving the distant mountain summits of Ben Loyal and Morven a softness as the clouds gathered at their nape. A deep inky pool called a dubh lochan, meaning “black water” in Scottish Gaelic, rippled in the morning light, reflecting the moodiness of the passing sky.

I was in Flow Country: the wild heartland of Scotland. Its name stems from the Old Norse floi, meaning “wet marshy ground”, and the area extends in a broad sweep from the mountainous ranges of the North-West Highlands towards the eastern coastline of the Moray Firth, covering 200,000 hectares between the counties of Caithness and Sunderland.

Already a week into my stay, I was volunteering for the Royal Society for the Protection of Birds (RSPB), helping the team with land conservation. The Flow Country is Europe’s largest blanket bog, a type of wetland formed from peat, and one of Scotland’s most valuable environmental assets. Almost 150,000 hectares is designated as a Site of Special Scientific Interest (SSSI), with the RSPB Forsinard Flows reserve caring for 21,000 hectares of it.

“If you’ve got any interest in climate change, restoring and protecting peatland should be very close to the top of your list,” said Joe Perry, coordinator of the Flow Country’s recent bid for Unesco World Heritage Site status. If the bid is successful, the area will gain international recognition for its environmental value. He explained, “It’s a habitat that is really underrepresented.”

It is not hard to see why. A “bog” doesn’t necessarily fit the visual narrative of, say, the Grand Canyon or the Great Barrier Reef. There is no “charismatic megafauna,” as Perry put it. Instead, “It’s about everything you can’t see; what’s underneath the surface.”

Blanket bogs began forming in northern Scotland at the end of the last Ice Age, around 10,000 years ago. Peat is formed when waterlogged layers of sphagnum moss and other vegetation only partially decay, accumulating and sealing in CO2 that would usually be emitted. These conditions have a cooling effect on the climate by acting as a “carbon sink”. The peatland in Flow Country alone sequesters about 400 million tonnes of carbon – more than double the amount in all the UK’s woodland combined.

If you’ve got any interest in climate change, restoring and protecting peatland should be very close to the top of your list

Peat has a long memory. Growing by 0.5 to 1mm each year, today the peat reaches 10m deep in places. The 20th-Century ecologist Frank Fraser Darling was right when he called the Highland peatland a “wet desert”. It’s filled with grassy hummocks and pale sea-green sphagnum moss, textured with tufts of dusky rose bell heather and pierced by acid-bright bog asphodel and slender blades of deer grass with painted cinnabar tips.

“The more you look the more you see” was a maxim I often heard used in relation to the peatland. This is a slow, granular world that eventually makes itself known. Its acidic, anaerobic conditions act as a natural preservative, as exhibited by its faithful cataloguing of social and climatic events across the Holocene. Among other discoveries, researchers have found fossilised pine stumps dating from 4500BC, remnants of an ancient forest that the Romans later called “the Great Wood of Caledon”; a Celtic War Horn from the 1st Century; and car exhaust particles from the 20th Century.

When we think of the “wild” we usually imagine vast tracts of land, pristine and untouched. In the US, spaces like these have been sustained through the 1964 American Wilderness Act, which protects landscapes in which “the Earth and its community of life are untrammelled by man”. But in Britain, although 34.9% of land is termed “semi-natural” or “natural”, these categories include areas impacted by human development. What little untouched land remains is mostly in the Highlands, of which Flow Country claims some of the last truly wild pockets.

I had never experienced the feeling of “wildness” before. Carrying out my tasks, trundling miles to collect wildlife camera SD cards from distant lochs, I soon found a simple happiness. As the fret of modern life collapsed, the natural world made itself heard and my dulled city senses began to wake up: the sonic vibrato of a snipe or the quick chirrup of a meadow pipit became deafeningly loud.

Flow Country is one of the least-densely populated parts of Western Europe. It’s possible to walk for hours without seeing another soul, with just the wind to accompany you. But the occasional sight of ruined flagstone houses lying open and exposed are stark reminders of the past. A time when Flow Country wasn’t empty – far from it.

Strathnaver is a lush valley running from Loch Naver to the northern coast along a salmon-blessed river. This was the territory of the historical Clan Mackay, and you can walk the 41km Strathnaver Trail through the deserted flagstone townships of Grummore, Rosal and Achanlochy. Once home to hundreds of people, these Gaelic-speaking crofting communities, formed by tenant farmers working small-scale agricultural plots, were evicted by the Duke of Sutherland in the 19th Century as part of a bloody episode that would become known as the Highland Clearances.

A few survivors clung to the lands, watching the hills become eclipsed by large-scale farms and their menacing “white tide” of sheep. During this time, pockets of Flow Country began to change as graziers drained and levelled peat for herds that roamed and plucked away at plant life vital to the area’s ecosystems.

You may also be interested in:
• The wildest edge of the Roman Empire
• The tiny ‘country’ between England and Scotland
• A new map revealing ancient Britain

One day at Forsinard train station, a small flagstone cottage with eaves painted cerulean blue, I met a retired nurse revisiting her childhood haunts of the 1980s. As we waited for the train that runs north from Inverness up the scenic coastline to Thurso, she recalled thriving markets and ceilidh dances at the quiet hamlet’s now-closed hotel. “I miss the sound of sheep,” she told me wistfully. “Everything changed with the trees.”

In the 1980s, the Conservative British government offered tax relief for investment in forestry plantations. Flow Country was selected as a suitable forestry site as it was considered a wasteland of no economic importance. Ancient peatland was further drained and furrowed at an alarming rate to ready the ground for monoculture plantations of lodgepole pine and sitka spruce. The trees rooted deeply, drying out the peatland and, in turn, releasing carbon.

The RSPB, alongside other NGOs and government nature conservation advisers, struck up fierce opposition to the plantations in what New Scientist magazine dubbed “The battle of the bog”. In 1988,  the government was pressured into discontinuing financial incentives, with further planting halted, but the damage was done: 17% of Scotland’s blanket bog had been drained.

I made several trips to see the plantations during my time in Flow Country. Just a short drive from Forsinard, the industry of forestry groups becomes apparent. Access roads were lined with piles of timber, portents of nearby commercial plantations, ruptured by thick furrows where harvester machines once ploughed into the landscape. In their wake, broken trunks lay scattered and left to rot. Near the hillside of Clais Gheal, I wandered about newer plantations neatly aligned in rows, eerily still and silent.

The arrival of these plantations in the 1980s gave rise to what is known as the “edge effect”. The borders of the forest provide cover for predators like hooded crows and pine martens, thus reducing the chances of native ground-nesting wader birds successfully breeding. Species like the curlew, with its witch-doctor beak and haunting “cur-lee” cry, have seen numbers drop in Scotland by 55% in recent years.

Dramatic losses such as these drive the RSPB’s urgent work in Flow Country, and they rely on public support to help do so. Volunteers, like me, contribute almost one million hours every year. Conservation work is tireless. The bulk of the work is spent carefully managing the deforestation of existing forestry crops that the RSPB purchased with the reserve in 1995. Trees must be felled to block drainage ditches, and dams installed to encourage revegetation.

It’s about everything you can’t see; what’s underneath the surface

As a volunteer, I was often dispatched to monitor water levels, both at managed restoration sites and comparative control plots of wild blanket bog. I was surprised at how much I learnt from the team members in a short timeframe – and how much I enjoyed it. I was taught the painstaking manner in which the organisation is restoring peatland; about the wealth of data that must be examined to execute the smallest of changes; and how my contributions will help damaged peatland return to its natural state, as a carbon sink, in about 15 years.

Nothing was more educational than being passed a garden rake. In the heat of the sun, I swept and swept in the knowledge that I was helping to restore a site of cultural and scientific importance. It was a small action that had a powerful resonance. The truth is I had arrived thinking I knew about climate change, but the physical experience of caring for a tract of land taught me more than I could have ever anticipated.

I remember pausing to watch the members of our little group, parsing away. We had all lapsed into a silence of contentment. I assume we were all thinking about the same thing: how difficult it was going to be to leave.

Future of Travel is a series from BBC Travel that investigates what the world might look like to travellers in the coming years and meets the people living on the frontlines of change.

Join more than three million BBC Travel fans by liking us on Facebook, or follow us on Twitter and Instagram.

If you liked this story, sign up for the weekly bbc.com features newsletter called “The Essential List”. A handpicked selection of stories from BBC Future, Culture, Worklife and Travel, delivered to your inbox every Friday.