Wading down the boulder-strewn river, hemmed in on both sides by thick jungle, I could hear the rumble grow louder. Oh man, I thought, here we go again.

This rumbling had become a familiar sound today and, like so many times already, was once again the unmistakeable roar of water crashing into the base of a waterfall. But this time - even before I had reached the edge of the cascade - the resonating thunder was loud enough to send the alarm bells ringing. By a long shot, this was the loudest set of falls so far. It could mean only one thing: the biggest waterfall yet. Even more alarmingly, once again I would be expected to blindly run off the end of it.

Before now, if I’d ever pictured myself hurtling off the edge of a 30 foot jungle waterfall it would’ve been immediately preceded by a hectic race downstream in an attempt to open the distance between me and at least 50 angry pygmies, each armed with blowpipes and machetes. But there were no pygmies here to coax out any unnatural airborne activity, for this was Central America. Instead, encouragement to leap came only from our magnificently bold (or slightly unhinged – you choose) eco-tour leader with personal liability insurance seemingly as robust as his nerves.

The theatre for my latest display of inherent stupidity was the ‘El Imposible’ National Park, a 10,000-acre rainforest nestled among the Apaneca Mountains in the province of Ahuachapan, El Salvador.

Following the success of 3 short excursions the previous day, I opted to hang around and check out more of what this fascinating area had to offer. And Tacuba, a small village located on the edge of the National park just a 2 hour bus ride from the Guatemalan border and 4 hours west from El Salvador’s capital, San Salvador, served as the perfect base from which to explore and learn more about the surrounding eco-wonderland.

Despite it being entirely possible to reside within the park itself (Bosque El Impossible National Park has designated camping areas with toilets and fire pits for those wishing to cook), Tacuba has become host to a growing number of accommodations to suit the budget of even the most frugal traveller. Not only did I get room for around 10 bucks, but it was also along the lines of a homestay, like a bed and breakfast in a private home, as opposed to a soulless box with minimal opportunity for social interaction. In such cases, you’d be hard pressed to put a price on the opportunity it presents – the opportunity to experience everyday Salvadoran family life from the inside.

From Tacuba it was simple enough to arrange guides. With so few visitors heading to El Salvador you are still treated like a visitor instead of a walking ATM, and, with sufficient Spanish (English is seldom spoken), it proves easy enough to ask around and receive genuine help and advice and be pointed in the right direction. Now, with guides readily available, all that was left for me to do was pick an activity.

Trekking has become an increasingly popular activity within the national park, and I wanted to check out what all the fuss was about - and since the park boasted at least 8 rivers and elevations ranging from 800 to 4,600 feet, a trek along at least one of them sounded just the ticket.

This is why, the following day, I found myself clutching a waterlogged black bin liner containing my unsuccessfully waterproofed daypack, and cautiously clambering over and around thigh high boulders and closer toward the edge of this knee-knockingly high waterfall. Around this time an all too familiar probing question once again reared its ugly head: What the hell have I got myself into this time?

My worst fears were soon realised. Peering over the edge I couldn’t help but notice the significant amount of fresh air between where I now stood – knee deep in the fast flowing river, teetering on the very edge of the fall – and the disproportionately small pool of water obscured by spray below.

You know how some folks refer to simple activities being ‘a breeze’, or ‘a walk in the park, well, I can assure you that these people are clearly deluded. Technically, this actually was a walk in the park, but I can’t for the life of me remember the last time such a ‘simple matter’ brought me to the verge of laying an egg in my pants.

With myself and 4 others gathered at the top of the fall, our guide dutifully pointed out the best angle at which to jump so as not require the services of either a stretcher or neck brace. Then, whilst waving his arms wildly and delivering something akin to an war cry by an Apache with Tourette’s Syndrome, he promptly disappeared over the edge. I stood for a moment, stunned by what I thought I had just seen. It just didn’t add up. Y’know, for a moment I could have sworn that he just jumped off the edge – but surely he can’t have, that would have been incalculable stupidity.

I glanced up and checked my fellow tour goer’s reactions, maybe they thought they saw it too. If incredulous looks could be likened to poker, this was a Royal Flush if I’d ever seen one.

Turning toward the edge of the fall, I lifted my chin just enough to peer over once again. I had hoped this time to see a happy, smiling guide treading water at the bottom and not something resembling an explosion in a butcher’s shop. Miraculously, I did see a happy, smiling head bobbing in the water, and the even better news was that it was still attached to its rightful owner.

As our guide swam toward the shallows (which, I must say, took a reassuringly long time) he flipped over onto his back and shouted up to the 5 bewildered gringos AKA ‘Team Terrified’ yet to make the jump.

“You must jump out far as you can…!” he hollered, looking exceedingly chuffed with himself and wiping the spray from his hair and face. Almost as an afterthought he followed up with “…And watch out for the rocks!” as if we weren’t already well aware of their unyielding, body-busting presence.

Lifting my day sack from the water, with its plastic ‘protection’ battered and torn by several encounters with boulders at the base of previous falls, I watched dolefully as rods of water drained from the various holes that now peppered it. After a slight backswing I heaved the waterlogged bag over the edge. There seemed to be painfully long pause between the bag leaving my hand and it splashing into the pool below. Naturally, this only added to my anguish. But at least it didn’t bounce off the rocks first.

Anyhow, I volunteered to go next. As I clambered to the edge on my dry run, I took great care to note precisely where my feet would go on the proper, albeit extremely short, run up. The rocks didn’t appear overly slippery and were easily negotiable even with the oversized sneakers our guide had kindly leant me that morning. This much is good, I thought.

After one final check of the area below I took a few paces back and then embarked on what I felt could have been my last few steps in Central America. Whilst eyeing up my stepping stones I blew out forcefully, as if to try and expel my anguish, and ran through the deed once more in my mind: three firm steps, a big leap, my own unique war cry, and possibly some kind of cool pose as I flew through the air with graceful elegance. Yeah, I was almost looking forward to this now.

Needless to say, the previous planning all went to custard the moment I set off for the edge. In events utterly beyond my control my eyes crimped themselves tightly shut, I ran like someone had just swapped my legs for two different sized pieces of industrial strength rubber, and, worst of all, I let out a ludicrously high pitched, irrepressible yelp as I pushed off into mid air.

In retrospect, I may have looked like a lot of things, but cool definitely wasn’t one of them. But, one by one as my fellow jumpers cleared the falls, I swiftly learnt that this wasn’t an uncommon reaction. It appears that throwing oneself off a waterfall with style and panache is somewhat a precious talent, and one bestowed solely upon a handful of fun loving (and slightly unbalanced) El Salvadorans.

As we swam back up through the cool, blue water to the surface, we knew we had done it. For the last three hours we had religiously followed the river’s course through the jungle, waterfalls and all, and successfully negotiated all that lay in our path. We had cheered and hollered and whooped and applauded as each of our new friends had cleared the jumps, we’d worked together to move along as a team – be it by linking hands or offering up long branches to ease each other safely down the steepest inclines, or by passing bags to and fro as frequently as words of encouragement – we’d placed our faith in each other as much as our guide and not been left wanting. So far this was a good day, but the adventure was far from over.

The last leg of the downward trek would include another bottle test. Yep, another waterfall - but one too dangerous to jump in rainy season. But had it been the dry season – between May and October – well, who knows… Instead, we would take the easy option and skirt around it. The easy option involved bouncing from tree to tree down a steep bank (picture those slot machines where you push a coin in the top and randomly bounces off uniform pegs on its way down behind the Perspex face – just like us, you never knew where the coin would end up) and then, with the aid of a thick rope set up by our tour guide and machete wielding scout, we negotiated a sheer rock face taller than your average house.

Our guide went first and showed us the drill. We looked on intently as there were only two ways down: his way, and the way that involved losing traction, missing the rope in blind panic, dropping 3 stories in as many seconds and, finally, spreading ourselves liberally over a wide and varied selection of rocky outcrops. As I said, he had our undivided attention. If secondary school physics teachers could emulate this guy’s knack of retaining an audience, we would now be living in a world full on NASA engineers.

“Slowly! Slowly!” he jabbered as he descended. Every now and then he would stop, hang off the rope, and point to footholds “Here…then here….then here” he would say, all the time eagerly nodding and delivering well received words of encouragement to 4 clearly concerned individuals. Our smiles broadened as our confidence grew.

Then, sucking the air through his teeth he announced “But not here…really, please, not here” - he even let go with one hand to shake his finger and emphasize the point. Our smiles drooped.

Standing at the bottom and, I dutifully noted, from a position well outside the potential gringo splatter zone, one by one he coaxed us down. Although it seemed a little hairy at the time, we knew we were in safe hands, and “slowly, slowly” we each made it down. After a little more handshaking and back patting we stopped for lunch at the base of the falls. Our scout divvied up the packed lunches and we sat on the rocks, conceivably in the middle of nowhere at the base of this magnificent waterfall, chatting excitedly, filling our bellies with cheese sandwiches and bananas, and recounting the highs of the trip so far.

Now came the tough part. We had descended a fair distance throughout the morning, and must now ascend back to our jeep at the edge of the park. The route back took us over new ground, through more rainforest and coffee plantations. Periodically we would stop on the inclines for a breather, squatting on the steep banks as we did so to either take in the views afforded by small breaks in the forest canopy or get a brief lesson on jungle survival from our knowledgeable scout. He would point out various plants, fruits, and roots, and relay - in Spanish - why and how they can be used. I felt inspired, he was like a skinny Ray Mears. Simply astonished at how so many different varieties of plant can all taste identical – like a subtle blend of rainforest soil and tree root – I was itching to learn more.

Though before I had a chance to dash off and find my very own piece of tree bark to gnaw on, our scout also pointed out some rainforest bad boys. We’re talking spiders the size of small coffee tables (would I exaggerate?), plants sporting spikes large enough to hang a coat from, innocuous, furry plants that if touched would even make chuck Norris cry and, curiously, a selection of toxicity on stalks disturbingly similar to the stuff we had already tasted. It was all a bit of an eye opener and, speaking from a bloke’s point of view, an educative round that appealed to me no end. But just like everyone who points out things that will ruin your day as soon as look at you, our guide qualified each statement with how they are only dangerous if you don’t know what you are doing or if you poke them with sticks.

Throughout the ascent we were told to keep our eyes peeled for wildlife, as apparently over 280 bird species - including the great curassow, the blue-crowned motmot (the national bird of El Salvador), and the king vulture - and a vast amount of other fauna including rare beasts such as pumas, ocelots and collared anteaters inhabit the area. Alas they went undetected, but the perpetual searching it did keep us quietly preoccupied - uncannily like how youngsters remain pacified by parents during long car journeys to the beach. Incidentally, I never did spot that illusive Cornish white rhino. I can only assume that, like so many of these rare animals, they must only come out at night.

Soon enough the dense canopy gave way to hillside coffee plantations and before long we popped back out on to the dirt track just yards from the jeep. Although astounded by this precise navigation, what I found infinitely more incredible was the tour itself - as from start to finish this had been an unparalleled experience. I mean that wholeheartedly.

It’d been less of an organised eco-tour and more of a schoolboy adventure. The whole day was incomparable in its nature to anything I’d experienced before. I could clearly picture our guide taking this very same alarmingly direct route down through the park as a child. We had meticulously retraced his steps through a previous adventure, albeit with less stick fighting, no plant poking, and some, but not as many, grazed kneecaps.