Before I discovered Guyana, flying over jungle countries used to depress the hell out of me. It’s always fine while you’re actually on the ground, tunnelling among the lush green caverns of the forest floor.

Down there, you can never experience more than the explosion of life, the sensory overload, which is evident within a few metres of you.

Watching a giant morpho butterfly flitting in the dappled sunlight like an electric-blue handkerchief; being hosed down with wee by a churlish howler monkey; happening across a tiny frog carrying its tadpoles to a bijou pond in a treetop flower... these countless small miracles wrap you up in the wonder of the jungle, and it’s easy to convince yourself that everything is well with the world.

Get yourself up in a flying machine, though, and it’s a different story. Now, you can see the wider truth – that some of the most famous and important jungle reserves in the world are actually smaller than an average-sized city.

Guyana's otter woman

On the banks of Guyana’s Rupununi River is a nature reserve with a difference, says Lindsay Hawdon

BACKGROUND

• Going wild in the Peruvian jungle

• Journey into remote Amazon jungle

• Twitching in Panama

• Conquering a virgin Venezuelan tepui

Their dwindling islands of forest are surrounded by fields, plantations or burnt and barren land, and logging roads penetrate deep into their recesses. Guyana is very different from that, however. A nation the size of Great Britain, its rainforest remains 85% untouched, and you can fly for several hours and see no roads at all, only rivers, glaring up like serpentine mirrors as the sun flashes across them.

Forest, forest, forest, in every direction, and not a sign of the country’s 750,000 people – because they mostly live in and around the drowsy coastal capital of Georgetown.

I’ve spent nearly two years of my life in rainforests, including time on every continent that has them, but I’ve never experienced one so benign as this – so free from plants that want to rip your clothes off, bugs that want to eat you and tropical diseases that make you spend your entire stay hovering over a long-drop toilet.

That said, I did get bitten by a vampire bat, stung by a bullet ant and shocked by a 200-volt electric eel. But it was still heaven.

For Guyana’s lucky few visitors, the excursion into rainforest paradise usually begins on the Upper Essequibo River, at the Iwokrama reservation, just a few hours south of Georgetown. There is an international conservation centre here, with a gaggle of tourist lodges, and its river journeys offer world-beating opportunities to see jaguars, primates and giant 20ft anacondas.

But I had ventured to Guyana with a TV crew, and our remit was to head for places that have never been surveyed before, where wildlife-watching is properly hard work. We made straight for the Kaieteur Falls, among the most powerful in the world, located in the Guiana Shield mountain range, where precipitous sandstone peaks jut up out of the most extraordinary rainforest imaginable.

Kaieteur is Guyana’s foremost tourist attraction – and yet almost entirely unspoilt. Near the top of the falls lie a tarmac airstrip and a small guesthouse, but planes arrive only every few days, and anyone choosing to stay here is virtually guaranteed to have one of the earth’s great natural wonders all to themselves.

That’s how it was for us. As evening cloaked the forest, we would wander down to wallow in warm pools above the waterfall, with the frantic orchestra of a million frogs chirruping, burping, quacking and strumming at the riverside. The falls thundered just metres away, tiny fish nibbled at our feet, and we felt like the only human beings on the planet. If the top of Kaieteur is pristine and wonderful, the bowl that lies beneath the cataract is very much an undiscovered realm.

When I visited, only two expeditions had ever penetrated the gorge below, and there is no record of them reaching the bottom of the falls. As we began to investigate the logistics of our expedition, we realised why.

It took us 800 metres of rope to rig up descent lines to abseil a three-person team down there, and waiting for us was an unimaginably hostile environment. I was the first to step off into the abyss, and immediately felt myself battered by gusts raging upwards – tremendous updrafts from the wind dragged over the falls. They brought with them surging, drenching spray, but this was nothing compared with what lay below.

After a free-hanging abseil from a cliff higher than London’s Canary Wharf tower, my feet touched rock so slippery it seemed to have been sprayed with Castrol GTX. Among its oily coating of bladderworts and other normally aquatic plants scuttled thousands of bright-orange land crabs, utterly fearless in a land too wet to harbour any predators.

That was only the beginning. We spent three days down there, and it felt like standing on the prow of a ship in a gale, pounded by unremitting hurricane-force wind and water – and this was supposed to be the dry season. It’s the closest I’ve ever come to getting hypothermia in the tropics, and jagged, slippery rocks tried to pitch us to our doom wherever we trod.

The bowl beneath the falls has not been dry for hundreds of thousands of years, which has created a remarkable environment. All around us, unique orchids and carnivorous plants bloomed, and I identified four separate species of frogs living in an utter paradise where they can breed at any time of year, no matter what the season. At least one of these is likely to be new to science.

And throughout, of course, we stood beneath the endless, lumbering cascade of water, which seemed to tumble from the heavens themselves. It is one of the most awe-inspiring places on the planet, and you can count the people who have ever been there on the fingers of one hand. Back at the top of the falls, we watched lurid orange birds dancing in the boughs, while the eerie roar of red howler monkeys echoed about the valley. Tiny golden frogs chirped from their homes inside giant pineapple plants.

I took a moment to contemplate the adventure we’d had, the places we’d seen. One day, a tourist invasion will surely descend on Guyana; it was a great privilege to have explored some of these secret places before it arrives. More than ever, I was struck by the vital need to play a small part in preserving these rainforests for our children to enjoy.

Steve Backshall’s programme Expedition Guyana will air on BBC1 and Discovery this spring

Travel brief: Guyana is best tackled using a tour operator. Responsible Travel (01273 600030, www.responsibletravel.com) has a 14-day tour from £3,345pp, including flights from Gatwick to Georgetown with BA and Caribbean Airlines, via Barbados or Trinidad and Tobago, and internal transfers. Or try Audley Travel (www.audleytravel.com), Andean Trails (0131 467 7086, www.andeantrails.co.uk), or Veloso Tours (020 8762 0616, www.veloso.com). For more information, contact the Latin American Travel Association (www.lata.org).

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