When Eleanor Roosevelt visited the falls of Iguazú in the 1950s, she took one look and said, "Ah! Poor Niagara!"
Poor Niagara indeed, for compared with the immense cataracts of Iguazú they are a dripping tap. But such is the power of American self-publicity that everyone knows of Niagara, relatively few of Iguazú. What popular fame they have attained probably stems from an appearance in the film The Mission.
For all its dynamic richness, Spanish has no equivalent for "breathtaking". Dictionaries all say "Impressionante". Not the same. Many stages of this Argentine trip are breathtaking, not least Iguazú.
As well as the jungle setting, the dark greens against the red basalt cliffs and the white thundering curtains of water, it is the sheer size of these falls that makes you gasp. They are 2km across and seem to go on forever.
There are two explanations for them. Our guide Chino, who has a lot of Guarani Indian blood, said that two young Indian lovers were canoeing downriver, escaping the wrath of a god when he made the riverbed collapse in front of them. As the lovers hurtled over, the girl turned into a rock and the man a tree standing over her. The other theory is volcanic, that it is is the point where the lava flow suddenly stopped. I don't go for this one myself, and anyway I've seen the girl's rock and the tree over it.
They've made it easy to see the falls up close with an extensive system of catwalks snaking around the cataracts. The lower falls walk could be the most beautiful 1,000 m in the world.
Jungle walks to the falls are filled with toucans, green parakeets, plush-crested jays, capibaras, coatis, and the brilliant metallic blue morpho and bright yellow-and-black swallowtail butterflies. With more than 400 species of birds and 2,000 plant species - palms, bamboos, orchids, epiphytes, bromeliads, strangler figs - it is an overdose of nature.
The falls change their character with the volume of water, gushing over with high water or, when the level drops, trickling like chains of pearls or fine lace curtains hanging off the cliffs.
The most violent falls, the ones Robert de Niro went over in The Mission, is the Devil's Throat. We took a boat out to the catwalk and went to a platform right on top of the booming cauldron with the deafening roar and the spray. This is the closest we get to standing on the edge of the world.
Chino took us late in the day, the best time, when the sun is low, lighting up the white churning waters of the Throat perfectly. Impossibly, swifts darted straight into the thundering waterfalls to their nests behind. We saw a kingfisher fly coolly across the foaming vortex through a rainbow hanging in the mists and a snowy egret glide impassively downstream.
In the middle of the river below and among the falls is an island, Isla San Martin. This place is heaven and you should head there as soon as you can. There is a short boat ride over to a beach then a path up into the jungle, round the island and into the falls.
At one end there is a red cliff with a window - La Ventana - through to some more falls beyond. Above the Window black vultures perch on the bleached branches of a dead tree and soar round the clifftop hanging in the hot air. If you ignore a "no trespassing" sign and clamber up through the window, which, of course, you should not do, a little plateau with great red boulders opens out in front of you, and there are swimming pools and waterfalls to stand under - this is paradise.
We sat in bowls bored out by the water in God's own Jacuzzi. We watched dragonflies - orange, bright blue, carmine - hang in front of our eyes and then dart off as the vultures' shadows skimmed over us.
Such is the wealth of plants and trees in the jungle that tour operator Aguas Grandes is organising a spectacular jungle safari. Chino took us through some of the flora, climbing up massive caña fistola - the highest trees in the jungle - with canopy rope traverses, and later abseiling down waterfalls.
On the river, the best trip is by inflatable up into the big falls. We went with an exuberant group of Argentines. We screamed and bellowed as we drove straight into the roaring, steaming cataract for a thorough soaking. The mighty power shower. "Otra! Otra! Otra!" they shouted like a football crowd, punching the sky, until the man headed back in for another percussive drenching. "Otra! Otra! Otra!"
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Yerba maté
Subtropical Misiones, where the great Jesuit missions were established, is the source of yerba maté, Argentina's national drink.
Maté is Quechua Inca for the gourd that the tea is sucked out of. Previously, the Guarani only used the crushed leaves for wounds, but the Jesuits wanted to wean them off their booze - chicha - and found it made a good stimulant drink. Luckily the indians took to maté and fashioned a bamboo tube, a bombilla, to suck the tea through.
I first got a taste for maté seven years ago on Isla San Martin. I had gone over early for the day and realised I had no food or drink. Two park workmen twice gave me some cold maté, and I felt no thirst for seven subtropical hours.
I spent the whole day cosmically involved with the waterfalls and wondered whether my friends had spiked my muesli with cucu melo mushrooms, or was it just the divine falls themselves? I may never know.
Driving into Misiones, the colours are intense, a red soil rich in iron against the dense green of rainforest and plantations.
Yerba maté is part of the holly family with shiny leaves like holly without the spikes. Picking yerba is hard poorly-paid work. Four hundred kilos a day is the maximum for an experienced picker. It earns him or her just $10.
Maté contains caffeine alkaloids such as mateine. It is a stimulant drink as strong as black coffee but as gentle as green tea on the stomach and constitution. It is apparently full of vitamins and nutrients.
The taste? It's bitter, organic, composty, some say tobacco-like. I like it. But it's one of those things like Marmite that you probably have to learn to love in the cradle.
I like the idea of carrying your tea around and drinking it any time, any place, although in Freudian terms the whole business is deeply suspect. Holding a warm breast-shaped gourd in the hands, taking a spout into the mouth, sucking out some warm fluid and feeling better hardly bears thinking about.
Best not worry. After all it keeps a great many grown men quiet down in the Southern Cone.
