Feel like a mate, mate

I still don't know why I ordered the maté. Was it curiosity, sheer bravado, a writer's earnest desire for empirical research; especially in a "Librobar", which is a quirky combination of public bar and reading room? Or was it simply a dare offered by our tour guide Gaetano, out of his capricious Neapolitan sense of humour?
Anyway, the drink duly arrives, borne by a grinning waiter. He obviously senses that the gringo who ordered it is completely out of his depth in the remote town of El Calafate, deep in the heartland of Argentine Patagonia.
My companions' faces are lit up in anticipation. "Okay, here goes nothing," I tell myself. I take a long sip from the steel straw, gag, choke and heave in quick succession. The sensation is extreme. Maté has a very bitter and astringent taste to the uninitiated.
"How was it?" the huddled group asks. My face clearly tells the story. I know this because everyone bursts out laughing.
I regard the bowl with the sort of disdainful look that says: "Did I pay 25 pesos for that?" Gaetano, a regular user who swears that the stimulant effect of maté enables him to work consistently for long hours, comes to my rescue by passing me a donation of five pesos and sucking up the entire bowl.
He tells me between regular sips that the green leaves of the maté plant provide the quintessential Argentinian social drink, full of vitamins and minerals. Whenever people get together here, they share a maté.
My reward for the tasting is a glass of pisco amaretto sour, a cocktail that also has the revered status of a national drink for special social occasions. It's also very intoxicating. As our convivial evening draws to a close, I'm very pleased with my introduction to local beverages and grateful to sink into a cosy bed in the benchmark hostel in El Calafate, the Hostal de Glaciar Libertador.
The next morning dawns bright and clear with a mild 12C temperature, which is ideal for the great adventure Gaetano has planned for us. Fortunately, the only beverage required for the day's outing is bottled water.
We pile into "Esperanza" (meaning hope), our trusty touring truck with its reclining airline seats, all-round visibility, intercom system, CD player and fridge.
Our destination is a remote corner of Los Glaciars National Park. At least it looks remote on the map. It's an hour's drive west of El Calafate. Here, there is little else but a few farm-stay estancias that offer lodgings for intrepid travellers.
When one travels to the uttermost ends of the Earth, one expects to find a great nothingness, devoid of humanity. On arrival at the Perito Moreno Glacier on Lake Argentina, we find the visitor centre alive with 300 travellers from around the globe.
We are encouraged to walk to the upper viewing platform to see the 20-storey-high terminal face of the glacier. Before I reach it, I hear a thunderous roar akin to the sound of an advancing train. Quickening my steps, I arrive just in time to see a block of ice weighing many tonnes slide down the face and crash into the lake, creating a billowing cloud of ice crystals that hang in the air, glistening.
Once the cloud settles, I look up and see the vast expanse of the Perito Moreno Glacier laid out before me. Its snowfield is visible 35km away in a basin encompassed by a series of jagged peaks. It sweeps down the broad valley in a graceful curve; twisted, fractured and split into bergschrunds and crevasses that trace a crazy pattern on the glacier's surface.
Descending to the lowest platform, I look directly out over a narrow channel at the 60m-high wall. Ice floes with aquamarine colouring and icecream texture are drifting through the channel into the lake. I'm staggered by the number of full-height cracks and fissures in the face, which give the impression that a collapse of the entire wall is imminent.
But it is not in the nature of glaciers to rush. The degradation of the terminal face moves at a truly glacial pace. I wait 20 minutes before another thunderclap reverberates across the void and up through the beech forest, followed by a huge splash. But this is merely a small chunk off the melting upper surface. The next big fall could be hours away. Sadly, I have to drag myself away from this mesmerising scene.
Our guide briefs us on the glacier, which, it transpires, is nothing less than a national treasure. It is one of only two glaciers in South America that simply refuse to subscribe to conventional wisdom about global warming. These two renegades with a Che Guevara complex insist on advancing when the universal cry is "Retreat".
In Perito Moreno's case, the vast catchment area in the Patagonia Ice Field gathers a huge amount of precipitation, which fills the nevé at a faster rate than normal. Consequently, every few years the glacier engulfs the rock-bound point of the Magellan Peninsula and blocks off a large arm of Lake Argentina. When the water behind the dam rises to around 10m above the lake level, the pressure is sufficient to lift the ice sheet off the bedrock, 110m below the surface.
A current below the ice gradually undermines it until a cavernous tunnel develops, and eventually the entire structure above the tunnel comes crashing down, sending a tsunami across the lake. This spectacular explosion of ice is a sight that people wait days to see.
Returning to El Calafate, we enjoy a fine meal of barbecue meats at Rick's Restaurant. Whole beasts hang over a raging fire in a back room and the maitre d' brings out a succession of succulent morsels of beef, lamb, pork, rhea and guanaco (a cousin of the llama). This excellent meal is served with wine, cider and the infamous pisco spirit, made from grape juice and pure alcohol mixed with lemon or lime juice.
It has been a good night in El Calafate, the "Capital of the Glaciers". It may not be Argentina's top party town, but there's usually a few bars where intrepid glacier watchers can relax and kick back.
I've learnt some new things during my stay - especially relating to mammoth glaciers and the cautious imbibing of popular national drinks. And there's a secret I must share about maté. First-timers should add lots of sugar - if only I'd known.

WEBSITES

www.adventureworld.co.nz
www.vivaexpeditions
www.glaciar.com

WHEN TO GO
The best times to visit are Oct/Nov and Mar/April, when temperatures are slightly cooler than the summer peak but there are fewer crowds.
THE GLACIERS
Perito Moreno Glacier is located in Los Glaciars National Park in southern Argentina, 80km from El Calafate.
El Calafate, on the shores of Lake Argentina, is a lively tourist town with lots of souvenir shops, cafes and restaurants serving excellent steak, lamb stew, pizzas and empanadas. There is over-the-counter banking, foreign currency exchange and ATM services.

GETTING THERE
LAN Airlines flies from Auckland to Santiago. Domestic flights connect Punta Arenas. Overland transport then takes you to El Calafate. Aerolineas Argentinas flies from Auckland to Buenos Aires. Domestic flights connect El Calafate.
Paul Rush travelled to Patagonia with assistance from Adventure World and Viva Expeditions