Most of the local boats that run up and down Tambopata River in the Amazon region of Peru are essentially powered by an engine not dissimilar to that of a lawnmower and the din they make shakes your bones and shatters the silence.

We motored upriver into the thickening jungle until the petrol ran out. As the engine cut, and the boat lost momentum, the driver steered us to a steep sand bank to refuel from a Coke bottle and for the first time we heard the sound of the forest. It came in a huge burst of bird song, hypnotic, enchanting and utterly foreign to our western ears.

The Tambopata region is easily overlooked by tourists. Most people who go to Peru visit Lima and Cusco and take organised rainforest trips from there to Manu National Park.

But it’s just as easy to take an internal flight to Puerto Maldonado, a frontier town with a feel of the Wild West. From here, you can book your trip independently.

Flying into Puerto is extraordinary. Once you get over the Andes, for as far as the eye can see, there is endless, green forest in an impossibly huge, unbroken canopy.

Gradually, the forest gives way to scattered farms, then suddenly, the plane is descending towards what looks like a field. Occasionally, they have to shoo the cows off the runway before you can land.

Unfortunately, logging is starting to take its toll in the region and the canopy is getting distinctly ragged wherever there is a road, but in the heart of Tambopata Reserve Park, you can still find primary rainforest intact.

From the airport, a motorised rickshaw will take you into town playing cheerful Peruvian music at full blast or you can wave down a scooter and hop on the back for a couple of soles; you might spot the odd sloth hanging from the electricity wires en route. Alternatively, if you book in advance, you’ll be escorted into town by a guide; not half as much fun.

You need just enough time in Puerto to invest in some wellies, sample the delicious local specialities of fried yucca and spicy cheese and book your accommodation and permit at one of the lodges strung along the river; if you reserve somewhere more expensive, you’ll be upgraded to a fast boat and avoid the lawnmower scenario altogether, although personally I am rather attached to this cheapskate way to travel.

Explorer’s Inn is one of the most famous lodges here. It has a world-record-breaking bird list of 620 species, a boat so fast it seems to hover over the water and, in Tambopata terms at least, pretty palatial accommodation with en suite toilets instead of a long drop at the end of the path.

There are plenty more lodges around if your budget is tight but Explorer’s was one of the pioneers here and their guides remain the experts at teasing out the secrets of the forest. The best way to do that is on foot, preferably early in the morning or at dusk, so come prepared with a keen desire to get up at 4am and return muddy, sweaty and delightfully worn out.

It’s worth the effort because these forests are teeming with life. The dawn chorus is a symphony played by a divine orchestra; your guide will pick out the different players, from the wolf whistle of the screaming piha to the bass undertone of the mot-mots and tinamous.

The howler monkeys also get into the musical act, the whole troupe bellowing a drawn-out howl that makes the hairs on the back of your neck rise. Tamarin monkeys flit through the trees 50 metres above your head, peering nervously down at the intruding humans.

A peccary (bristly native pig), tapir or a tamandua (anteater) might cross your path and occasionally, one of the cats: a puma, a jaguar or the beautifully patterned ocelot.

But even if you don’t see the bigger species, with a good guide, it’s impossible to get bored in the forest. There are trees that can walk, although admittedly their progress is fairly slow. The trunks balance on a wigwam of roots; cautiously and slowly, over the course of weeks, new roots head out in one direction.

When the tree is balanced, it withdraws the back roots and moves forward so over the course of a few months, it appears to have scuttled across the forest floor.

The ant tree is another curiosity. It’s easy to spot because it stands in a completely cleared patch of forest floor. In exchange for a safe home in the trunk, the ants systematically clear all competing vegetation so that the tree has space to grow.

Flying into Puerto is extraordinary. Once you get over the Andes, for as far as the eye can see, there is endless, green forest in an impossibly huge, unbroken canopy

There are also beetles as big as a man’s hand with horns like a rhino, bugs disguised as peanuts and ants with a venom as strong as a snake; get bitten by one of those and you’ll spend the rest of the day in bed, as a fellow traveller discovered.

The Tambopata is one of the few places in the world where you can glimpse giant otters in a tranquil ox-bow lake. Watching these sleek, animated creatures floating on their backs to eat a freshly caught fish or cuffing each other playfully is one of my favourite memories. It’s easy for the otters to get spooked and they’ve been known to desert lakes entirely after disturbance, so encourage your group to keep quiet in advance.

At night, the forest changes completely. It’s a good time to see the big cats but even better for night birds; the eyes of nightjars glow scarlet in the torchlight as they sit, transfixed, on the path; frog-mouths roar their inimitable calls to one another and owls flit over the canopy. A friend had a snake lash out at him from a tree; fortunately fangs and venom hit his head torch instead of him, but it was a close call, so proceed with caution.

Most of the lodges are located in the Tambopata Candamo Reserved Zone, but the most pristine forest is located much further upriver in the heart of the Tambopata Park itself.

Here at the Tambopata Research Centre lodge, you can see one of the true wildlife spectacles of the world: a clay-lick (colpa), which attracts literally hundreds of blue and yellow macaws, scarlet macaws and countless parrots.

The birds are attracted here to eat clay from the walls of the river; it helps them eliminate the toxins from some of the seeds they eat and this is pretty much the only place to get it. The flashes of countless magenta, indigo and ochre wings against the iron red of the cliffs and the deep green of the tangled forest are an unforgettable sight. The birds finally leave at dusk, silhouetted against the setting sun.

I always left this fabulous forest with mixed feelings. There was one more bird I wanted to see, a jaguar to track down or a capybara to watch again; delving into the tropical greenery exerts an endless attraction.

But the rainforest is a tough place. The humidity, the mud, the truly vicious, biting insects all take their toll. When you get back to Puerto, the shabbiest of local hotels will feel like a palace, but you’ll dine out for weeks on your jungle stories.