Last month, President Hugo Chavez proclaimed that Venezuela would have a new time zone. Having already redesignated the country a "Bolivarian Republic", redesigned the flag and created a new currency, he announced that the South American nation's clocks would be turned back by half an hour. There is, however, a part of the country where time already seems to stand still: the vast area of land known as the Gran Sabana. These 15,000 square miles of rainforest – nearly twice the size of Wales – were virtually inaccessible until three decades ago. And among those with an adventurous turn of mind, the area is commonly known as the Lost World.
It's dominated by about 100 vast, flat-topped mountains called tepuis. These table-top, cliff-edged giants soar up to a mile above the jungle, and the sandstone that forms them is more than two billion years old. This means that the tops of the mountains themselves have been isolated for millions of years.
Mount Roraima is arguably the most famous of the tepuis, because it was the first to be explored. Fifty per cent of the flora and fauna on the summit is found nowhere else on Earth, and much of what is to be found here has yet to be documented by scientists.
In 1877, while the debate over Darwin's theory of evolution was raging in England, the Spectator magazine asked, "Will no one explore Roraima and bring us back the tidings which it has been waiting these thousands of years to give us?" But it was another seven years before two British explorers, Everard im Thurn and Harry Perkins, would make the first successful summit of a mountain deemed unclimbable by Sir Walter Raleigh. Even today, only a handful of the tepuis have ever been explored.
It was after listening to a Royal Geographical Society lecture about Thurn and Perkins' daring expedition that Sir Arthur Conan Doyle penned The Lost World, his tale of a land still inhabited by dinosaurs. Life imitated art, and the area soon adopted the name of the book. Today, the region is best known as the home to the tallest waterfall in the world, the Angel Falls, which cascades off another of the table mountains: Auyan tepui. The legend of its discovery would have provided a perfect case for Conan Doyle's best-known literary creation, Sherlock Holmes.
The story goes that in 1921 Jimmy Angel, an accomplished pilot, met an Alaskan prospector named JR McCracken in a Panamanian bar. McCracken regaled him with a tale of a mountain of gold in southern Venezuela, previously documented by Portuguese explorers and by Colonel Percy Fawcett, a British explorer who later went missing forever in the uncharted jungles of Brazil (and who became the inspiration for Indiana Jones).
The following year, the two men headed south and eventually landed on one of the tepui. McCracken used an old compass and map, and picked out a flat spot on which Angel was able to land the plane. Then McCracken waded into the river to fish out vast nuggets of gold. The pair worked fast and loaded more than 75lb of ore, but daylight was fading, so they had to leave with just a fraction of the available gold deposit. McCracken sold his haul for thousands of dollars but fell ill and died a few days later, leaving a distraught Angel to spend the rest of his life trying to relocate that mountain. On one ill-fated return expedition, he crashed into the jungle and spent 11 days hacking his way back to civilisation; it was in 1935 that he discovered the 3,212ft falls that would later bear his name. He eventually lost his life in 1956 when his plane flipped over – his ashes were scattered over the Gran Sabana in the hope that they might rest with the gold that had eluded him for 35 years.
As a child, I was as smitten with Angel's story as I was with Conan Doyle's mysterious Jurassic world, teeming with prehistoric beasts. It seemed astonishing that mankind had explored the deepest oceans and even set foot on the moon, and yet this vast area of the planet's surface remained largely unknown. I vowed that one day I would visit the Lost World for myself, be it to discover gold, dinosaurs or something else altogether.
Last year, I was finally given the opportunity when I set out on a number of expeditions to the furthest corners of the world – from Papua New Guinea and Nepal to Libya and Uganda – for the BBC series Extreme Dreams, in which I lead teams of novices on a series of extraordinary journeys. One of these treks involved climbing Mount Roraima, the 8,986ft tepui in Gran Sabana which also forms the tripartite border of Venezuela, Guyana and Brazil. And so I set off, clutching a battered copy of Conan Doyle's book.
Unsurprisingly, getting to the Lost World is not easy. A flight via Amsterdam and Aruba in the Caribbean eventually deposited me in muggy Caracas, whereupon I transferred for the two-hour flight to Ciudad Bolívar in the east of the country. This was followed by another three-hour flight by Cessna to Santa Elena de Uarien which included a layover in Canaima because of exceptionally heavy rain. Then, after one final bone-crunching, off-road car journey, we reached our start point at Peraitepuy, a Pemon village and the most popular start point for those on their way to Roraima.
Although the trek can be done in three or four days, we had devised a longer 10-day expedition that included navigating through some of the region's denser jungle and winding rivers. I wanted to push my team a little harder than is ordinarily done on this trek, to create an even greater sense of achievement, and to give them a real chance to take in this unique and beautiful landscape.
The surroundings were more open than I had anticipated: savannah dotted with palm trees and rivers – and it soon became apparent that two things were going to dominate our adventure: water and puri puris.
Water is a key feature of the Gran Sabana, with each tepui generating its own weather system. It rains a lot, and we had to make plenty of river crossings. But while rain and water can generally be managed with the right equipment, puri puris are seemingly unstoppable. They're the Houdinis of the insect world: tiny gnats, able to get in and out of any material and known locally known as plagas, meaning plagues. Try crossing a Scottish midge with a Scandinavian mosquito and you'll get some idea of how unpleasant they are. They are also seemingly immune to all repellents and clothing. They drink 100 per cent Deet like orange juice, and bite through midge-proof clothing like butter. On my first day, I counted 150 bites on my ears and arms alone, and my left eye had swollen closed as a result of their attacks. We pressed on through these biting clouds until our bodies could itch no more, sometimes resorting to smearing mud on our skin in order to create another barrier.
It was five days before we caught a glimpse of the fabled tepuis, two vast fortresses of rock soaring into the sky. The nearer, Kukenan tepui, has been closed to trekkers and scientists alike for several years since an adventurer and his guide went missing on the summit. The other was Roraima; it loomed in the distance like an impenetrable fortress.
Both certainly looked ancient, and rose from their surroundings like huge land-islands. I found myself almost mesmerised by their scale and beauty. It seemed extraordinary for such isolated pinnacles of rock to dominate an otherwise flat savannah. We're used to seeing mountains in ranges, creating a rolling or jagged horizon. The tepuis, however, looked more like objects forgotten by giants. (Indeed, local lore has it that they are the remaining tree stumps left from a greedy giant who tried to cut down two vast trees for his fruit. The trees fell into Brazil, creating their rich rainforest, and leaving just the stumps for the gluttonous giant.)
We trekked for up to 10 miles a day as the weather alternated between steamingly hot tropical and steamingly wet tropical. The rivers were swollen by the heavy rainfall, often necessitating the use of ropes to cross them. During our journey we also paddled down rivers in dug-out canoes and fished for piranha. The rivers are like highways through the vast savannah, and it was a welcome relief to take to the water and enjoy the change of scenery. We often found ourselves accompanied by a flotilla of tree trunks and jungle detritus in the rivers, which had been swollen by heavy rain and were brown with run-off from the hills above. This whole area is a national park and fishing is only permitted with government licences. But even with a licence, it felt pretty strange fishing for piranha with primitive bamboo rods and crude lines.
After a week's trekking across the savannah from Peraitepuy, we at last reached Roraima's base camp, which is set at an altitude of 6,234ft above sea level, but is still only at the foot of the tepui. As we pitched our tents, ready for our summit attempt, the camp was bathed in tropical sunlight. This was soon superseded by an enormous thunderstorm, which sent a torrent of water through the middle of camp and inundated my tent.
By now, our bodies had been baked, bitten and soaked in equal measure. As we shared a large spaghetti Bolognese for our last supper, I began to see why this Lost World had remained lost for so long.
We set off early for the ascent. The track passes through a number of climatic zones, including a thick cloud forest. The jungle here is also home to an army of venomous snakes, including the bushmaster, fer-de-lance and the rattlesnake, but it is the mapepire – also referred to as the bothrop – that has the most fearsome reputation, and is responsible for more fatalities than any other American reptile. These fearsome snakes infest the forest, often hanging from trees and striking unsuspecting passers-by. So terrified of them are the locals that a number of our porters refused to continue from base camp. As we pressed on with our experienced guides, I thought that the snakes made a fittingly Indiana Jones-type of threat.
Thick cloud clung to the side of the mountain, dousing us in freezing rain and turning the trail to mud. The forest was covered in a thick blanket of moss and lichen from the damp climate. Dangling vines looked worryingly like snakes, and created a forest-scape that was reminiscent of something from a Brothers Grimm tale. We edged our way along a rough trail, which by now had turned into a cascading stream. Thick mud clung to our boots as we waded through rivers and clambered up the steep path.
Onwards we slipped and splashed until we reached a vast waterfall cascading off the summit, which itself was hidden in thick cloud. Eventually, the vegetation thinned and we reached "The Wall" – a 1,300ft cliff of quartzite, which dwarfed us like ants. Many early explorers had turned back here, defeated by the sheer face. Luckily, we knew we wouldn't have to climb it as – in the manner of a good Conan Doyle novel – there is a secret gateway called "The Ramp", discovered by Everard im Thurn and Harry Perkins in 1884.
One of the few vegetated parts of the mountainside, the ramp bypasses the wall and leads to a fissure in the side of the mountain, from which a steep scramble takes one to the summit. The narrow plume of a waterfall cascading off the summit creates a sort of portal onto the ramp. In really heavy rain, it is sometimes impassable due to the power of the falls under which one has to walk, like a giant shower. Slowly we wended our way along the narrow trail before we zig-zagged our way up the final trail and onwards, above the cloud.
The view was astonishing as I clambered onto the summit. The scenery at the top of the mountain is like a moonscape from a B-list sci-fi film: impressive blackened rocks of every shape and size interspersed with tiny, colourful gardens. The anarchic landscape is fissured and eroded and scattered with deep gorges and chasms, babbling red rivers, glistening white crystals and pink sandy beaches. It is at once surreal, eccentric, beautiful and dreadful, like some crazy, drug-induced Dali painting.
The surface of the summit of Roraima covers 13 square miles. In the past, adventurers and explorers have been lost for days in its rocky maze; some, less fortunate, have been lost forever. Rescue helicopters are rarely able to land, due to the extreme conditions.
The rock formations create the illusion of preposterous shapes. Everard im Thurn depicted the summit as an "apparent caricature of umbrellas, tortoises, churches, cannons and innumerable other incongruous and unexpected objects". I saw profiles of my friend Charley, one of Fidel Castro, and even one of my wife's Christian Louboutin shoes.
The rolling mist added to the eerie and otherworldly scene, as it funnelled up the sheer rock face like smoke. Pterodactyls wouldn't have been out of place here; indeed, some say that these were among the pterodactyls' final nesting places before they died out. Local lore insists that dinosaurs still inhabit these high-altitude "islands". It's certainly the case that plants have adapted to these surroundings in an evolutionary trend that reflects the nutrient-poor soil. Up here, a carnivorous bromeliad has evolved tube-shaped leaves that create water-filled death traps for unwary insects.
Up and down, over the rocky surface, our guide escorted us carefully through the maze of sand-blasted sculptures. For three hours, we trekked in silence until we reached the ironically named "El Hotel", a cave system used by climbers to shelter in overnight, in the freezing mountain temperatures.
I pitched my tent on the soft, sandy floor of the cave as the heavy rain once again enveloped the mountain, creating a watery curtain at the cavern's entrance. The puri puris had left us at the base of the mountain, and the thick, tropical air of the savannah had now been replaced by the chilly temperatures of the mountains as thick cloud rolled in and out like waves. The cave certainly created a warm shelter as we sat around the camp stove (open fires aren't permitted; neither is the removal of anything from the summit) eating rice and beans and discussing the trek. We were alone on that mountain top, and for just one night, we felt like pioneer explorers visiting a new, unexplored land.
I had fulfilled my childhood dream. I may not have seen a Tyrannosaurus rex, but I'd sighted the rare grillo de agua – a water cricket that can inflict a painful bite – and even glimpsed the Oreophrynella quelchii, a tiny black toad so primitive that it neither swims nor hops, it just crawls.
Conan Doyle's characters left their Lost World through a secret cave. I would be taking the more conventional hike down. But for now, the Lost World had finally become a reality. Or had it? As I closed my eyes I saw a herd of Diplodocus drink from a river of gold – and the real world once again became the stuff of dreams.
'Extreme Dreams with Ben Fogle' is on weekdays at 6.30pm on BBC2
To get to Venezuela from the UK, you can fly via mainland Europe with Air France/KLM (08705 074074; www.klm.com) or Iberia (0870 609 0500; www.iberia.com). Air Europa (0870 121 3413; www.air-europa.com) flies from Madrid. Delta (0845 600 0950; www.delta.com) and Continental Airlines (0845 607 6760; www.continental.com) fly via the United States.
To reduce the impact on the environment, you can buy an "offset" through Abta's Reduce my Footprint initiative (020-7637 2444; www.reducemyfootprint.travel).
Tours are operated by specialists such as South American Experience (0845 277 3366; www.southamericanexperience.co.uk). Its 15-day Venezuela – The Lost World trip costs from £855 per person. The itinerary takes in Ciudad Bolívar, Canaima National Park, Angel Falls, the Orinoco delta and Caracas, and the price includes guided excursions, hotel and guest house accommodation, transport and some meals. An additional six-day trek to the summit of Mount Roraima can be added from £484. International flights are not included.
Geodyssey (020-7281 7788; www.geodyssey.co.uk) also organises a 13-day Trek to the Lost World from £1,225 per person, including transfers, guides, excursions and accommodation with most meals, but not including international flights.
www.venezlon.co.uk; 020-7387 6727
www.lata.org; 020-8715 2913