The Amazon amazes in its everchanging majesty, and I‘m travelling it in majestic style aboard the MS Explorer. The Explorer is recognised as being among the world‘s finest expedition cruise ships, custom­designed to handle climates from the rigours of Antarctica to the steamy sweat of a tropical jungle. There are just 48 passengers and a crew of 56 to more than cater for their every need.

A special feature of Explorer trips is the onboard inflatable Zodiacs, sturdy rubber dinghies with outboard motors that can negotiate the narrowest tributaries. For five or six hours a day we take to the Zodiacs, purring along little side channels, exploring flooded forests, or mooring and then hiking through the incredibly rich rainforest which characterises the Amazon system. The trip begins in Iquitos, the languorous river capital of the Peruvian Amazon. The bizarre is commonplace in Iquitos, such as the funky Regal Bar which also serves as the British Consulate, or the waterfront Fitzcarraldo Bar, which instead of evoking memories of the Irish adventurer made famous in the movie Fitzcarraldo is a modern, art deco pub of chrome and glass.

The focal point of the city is the Plaza das Armas, from where a short stroll along the riverfront leads to the tree­lined Plaza Ramon Castilla. From here, a grunge­front stroll ends at the new Plaza de la Amistad Peruano­Japonica, a memorial to two Japanese kayakers drowned during an Amazon expedition in 1997.

As we hit the river, we already sense that this trip will be a nature­fest without parallel. Aboard the Explorer is a team of guest naturalists and lecturers which would make the National Geographic Society green with envy.

Statistics about the Amazon River nearly defy belief. Suffice to say that the discharge of the river is over 6000 cubic kilometres of water a year. Jacques Cousteau once calculated that around 400 million tonnes of silt are discharged each year from the mouth of the Amazon River.

Is there an upper limit to the ingenuity of nature, any bounds to the processes of evolution and devolution¬ If so, these boundaries must surely be right here in the Amazon, with its seemingly limitless variety of species. Over 50,000 plant species (one fifth of all the known plants in the world) are found in the Amazon region. Among them are weird cacti, which, according to the rules of botany, shouldn‘t be here; the delicious fruits of the cupuasú and asaí trees, and the as yet little­known hallucinogenic plants of the psychotrea family. Everywhere you look, lianas twine around age­old trees, rare orchids peep from behind tree ferns, and bromeliads perch high in the treetops. Strange animals and birds abound, too, from sloths and squirrel monkeys to raptors, toucans and macaws, as well as world‘s most prolific collection of beetles. At twelve times the output of its nearest competitor, the Mississippi, the Amazon counts among its tributaries the Madeira (itself with twice the output of the Mississippi), the Rio Negro and the Isa. Australia‘s Murray may be the world‘s fourth biggest river system, but in comparison with the Amazon it is a mere elongated puddle. The Ampaiyacú River is an important tributary, branching off the Amazon about a third of the way between Iquitos and the Brazilian frontier. The main town on the Ampaiyacú, Pevas, is said to have been founded in 1542, making it the oldest European settlement in the Western Amazon. The Boras and Huitoto tribes, to whom this is still prime heartland, naturally trace their roots back much further. Our expedition leader is Suzana Machado d‘oliveira, a charming sadist who wakes us at 5:30 in the morning for pre­breakfast activities. Suzana is a native of Brazil and a wonderful authority on the Amazon, having spent many months travelling in small boats all along the river, scouting for new places for privileged passengers to visit. Pichana is explorersterritory. At six in the morning (are we all masochists¬) we take to the Zodiacs, cruising the Pichana River. Our guide, Chris Cutler, is a nature freak, with degrees in ornithology and an encyclopaedic knowledge of the Amazon Basin. Taking us for a walk along a jungle track, he points out rare birds and bugs, including the little nasty that causes Chafa‘s disease, which plagued Darwin in his later years. Leaving Peru and entering Colombia is as simple as changing a shirt, thanks to our efficient crew. Amazonas is Colombia‘s largest province. It is 110,000 square kilometres in area, yet the country‘s frontage onto the Amazon River extends a mere 130 kilometres. Despite the narrow river frontage, Amacayacú National Park is a huge reserve, covering some 1700 square kilometres. It‘s a brilliant, sunny day in downtown Leticia, the capital of Colombian Amazonas. At the Club Monaco Casino, frontier characters looking like leftovers from a John Wayne movie sprawl at sidewalk tables. Lithe and highly desirable young ladies from Tabatinga, a Brazilian town just across the border, drive past on their mopeds and in cutdown Volkswagens. The melting pot here seems to be constantly on the boil ­ and visitors are advised not to stir! Life in Leticia centres around the markets, with a general market to the west and the fish market right in the centre of town ­ a great place for a fish market! At Tio Tom‘s I down a couple of beers with two locals, Jose and Luis, who are masters of the art of winning the confidence of visiting travellers and tourists and then gently fleecing them. The whole operation is so painless that you hardly feel a thing. I‘ve even line up for more. Unfortunately, it‘s time to leave Colombia and cross another frontier, this time to huge Brazil, the fifth biggest country in the world. Lake São Paulo, just over the Brazilian border, is near the trading settlement of São Paulo de Olivensa. Over the lake, a latticework of tree canopies and giant strangler figs filters the sun‘s rays into surreal light shapes. The flooded forests of the Panela River, also called the Parana das Panelas, present an amazing spectacle. In May the river is a full ten or twelve metres higher than in October, forcing settlers to build their houses on floating pontoons. Squirrel monkeys climb in the branches of seemingly waterlogged trees, while three­toed sloths and rare birds, such as the masked crimson tanniger, are concealed in the canopy. In the early hours of morning, we creep along the blackwater Rio Jutaí, mooring near Foz do Jutaí, a prosperous settlement which sprawls over a couple of hills that rise from the riverbanks above the waterfront fish market. I‘m 72 years of age,says Señor Francisco Marche do Santo, the owner of the ramshackle Curajão Bar in a little side street of town, and I‘ve never had any reason to leave here. He has enjoyed a lifetime of jungle serenity, broken only by the hundred decibel samba music that now blares throughout the town. The Curajão Bar serves a potent brew of cachasa, firewater so strong it nearly eats through the glass. I was about to ask if you get a free seeingeye dog with every shot, when my tumbler was topped up again, this time with the addition of abacaxi, freshly squeezed pineapple juice. Foz do Jutaí is a thoroughly pleasant and well­maintained little place to stop over in. A couple of good hotels, including the Tuchaua Palace Hotel, offer air­conditioned rooms, and there are a few good, casual restaurants nearby. With the village square being a great place to hang out, Foz do Jutaí could make an ideal base from which to explore the local river system. Swimming here is also very good, as the black wateris too acid for piranhas. If you swim elsewhere in the Amazon, you just have to hope that the fish are vegetarians! Later, we get the chance to cruise the flooded forests. In a sensational day of exploration, we visit places previously unknown to even our guides, with new vistas of the flooded forest, and the riverine village of Estrela da Pais, where a vivid, cobaltblue church sits right on the waterfront, and flocks of macaws swarm like bees. This is the Amazon at its most raw. Under the gunmetal sky of early morning, the fishing boats on Lago da Uara look as if seen through a fine, grey, mosquito net. The trail through the village passes plantations of brazil nuts, harvested and stacked ready for sale to a roving buyer. Downriver, Cuxiu Muni marks the junction of the Parana do Capivara with the Amazon. Sunset and sunrise appear to follow one another as though night had never occurred. However in the intervening hours we hit the Zodiacs once again. We spot three­toed sloths, the most friendly and placid animals you will ever find, with a face like ET, and which seem to delight in being held and fondled, along with boa constrictors and caiman, while fireflies randomly zap the night sky. Irena, the village midwife in the nearby settlement of São Francisco da Boca do Capivara, is seventy years of age, weather­beaten yet poised and serene. She has delivered over two hundred children over the last forty years without a single mishap. Life in São Francisco is simple, revolving around fishing, gathering brazil nuts, for which the price has quintupled from 1998 to 1999, and making farinha, or flour from manioc, the local root crop. Dona Maria‘s son, Raimundos, heads the local soccer team in this football­crazy nation. Wearing a Bananas in Pyjamas tee­shirt, he explains his team‘s success we‘ve played in Manaus,he says, but never in the national league. It‘s difficult to get good coaching here. For secondary schooling, children can attend high school in the town of Tefe, about an hour away by speedboat. But few choose to do so. Downstream from Tefe we make top speed to reach Manaus, a city of about two million people, in time for the night‘s opera performance ­ humungle in the jungle, as seemingly out­ofplace in this environment as it was when the Opera House was first built, back in 1896. But just before reaching Manaus, there‘s time to witness the world‘s most spectacular confluence, as the dark waters of the Rio Negro meet the silty waters of the Solimões, forming spectacular swirling patterns, like a spoonful of ink dropped into a glass of cloudy beer. The patterns persist for many kilometres downstream before the two streams finally merge. Manaus is a great place to spend a few days. Despite its big­city feel, you sense the jungle all around, and the river seais so all­embracing that it‘s hard to remember you‘ree still inland. Sadly, I have to leave the Explorer in Manaus. On this trip, the Explorer continues on to the mouth of the Amazon at Belem. Somehow, you can‘t help feeling that, like the Amazon itself, the Explorer will still be rolling along many years after her bigger but less inspiring sisters have been consigned to the scrapyard.