With wild cries, El Pato's conquering army galloped up the hill and planted the blue-crested flag of Mendoza in the thin soil of the high Andean desert.
Mission accomplished: our raggle-taggle band had followed the route taken by the great liberator, General San Martin, in 1817 from the wine city of Mendoza to the Chilean border.
The previous year, Argentina's best-loved hero secured independence from Spanish colonial rule for his country, then known as the United Provinces of South America. In 1818, with a little help from Bernardo O'Higgins, once a fellow pupil at an exclusive school in Madrid, he did the same for Chile before turning his attention to Peru and Bolivia. But first he had to get there, a ride without maps past Aconcagua, the highest Andean peak.
Today, his route appeals to patriotic Argentinians and enterprising foreigners in search of a no-frills riding and camping adventure. Enter El Pato (The Duck), the resourceful owner of Cabalgatas Cordilleranas, a Mendoza-based company specialising in historic rides. Appropriately, his real name is Martin Cavallo (horse in Italian), but his nickname, well suited to a sunny character with an answer for everything, has stuck.
When I arrived in Mendoza, my fellow English speakers were lined up in the street outside the hotel. There were the cousins Pete and Liam, tough stockmen from rural New Zealand; Neil, a midwife turned computer specialist from Melbourne, dressed to kill in poncho and Stetson; and Marcello, a quiet German-Swiss.
The next morning we were joined by Angel, North Face's travelling rep in Argentina, and Maria, an elegant estancia owner. In Las Hornillas, described as a simple mountain refuge but revealed as a shack with curs barking, hens pecking and rough pasture to camp in, we made our first attempts to put up our tents in bad weather. Eager Argentinian hands assisted Angel to assemble his waterproof palace, while the foreigners struggled unavailingly with their basic shelters. No matter. Needs must, we would improve. Morale was boosted by an asado, sides of succulent beef roasted over an open fire by Alejandro, aka El Gallina. That loosely translates as Male Hen, but Peacock would better suit this showboating former professional footballer turned travelling gaucho. And yet, he is a resourceful chef and, with the help of few bottles of Mendoza's rich malbec red, the show was on the road.
The spectacular nature of that road was revealed at sunrise as the horses were saddled and mules loaded with provisions for the next eight days. My skinny grey, Fantasma, and I joined the trail and headed, most reluctantly in his case, for the rocks. The first day was a gentle introduction, five hours in very comfortable saddles along dramatic cliff paths to the mountain camp at Manantiales (2,600m).
Pato and Gallina launched the next day's journey with the Argentinian national anthem, equally available to San Martin because it was written in 1813. Like us, the Liberator left Mendoza in January, the middle of a three-month window when the high passes are snow free. His Army of the Andes included 4,000 men, 1,000 horses, 30 cannon, 10,000 mules and 1,200 auxiliaries to manage them. He reached what is now Chile in time to win the battle of Chacabuco on 12 February.
The highlight of our eight hours in the saddle, a gruelling sector with serious ups and downs, was our first sight of Aconcagua, a snow dome 6,962m high that's partially lost in swirling cloud. On the way up to the 4,500m pass that revealed it, we crossed and recrossed the turbulent Las Lenas River, pausing for a picnic lunch of delicious cured ham, cheese and salami. Herds of guanaco picked at much sparser fodder on vertiginous brown and gold shale slides high above the valley floor, while condors dive-bombed from above: the piles of large whitened bones along the route testified to their enthusiasm for free meat.
At the end of each day, the animals were released to graze upon the slim pickings on barren hillsides while the gauchos scavenged for firewood, also in short supply as most of the route is way above the tree line. As soon as the flames were glowing, they settled down to an excitable three-hour chin wag, accompanied by mate (bitter Andean tea) and malbec, while Alejandro made a fortifying one-pot dinner.
Our third day in the saddle brought us into the Valley of the Ducks, named not in tribute to Pato but after the water birds that gather there in spring. We reached the base camp for our assault on the frontier at dusk, seeking out spaces in the remnants of a very basic military outpost to set up the tents for our three-day stay. Here, the river provided a chance for total immersion in icy water, and some trout fishing.
The next morning, Pato, his furled banner at the ready, marshalled us for the final stretch. En route we came close to mighty Aconcagua. Three hours later, we urged our horses into a rare canter at the sight of twin busts of San Martin and O'Higgins set on a plinth in the wilderness.
So this was how Mendoza conquered Chile, and we posed for photos next to the flag to mark our achievement. General San Martin was 38 years old when he reached this point. He rode on to fulfil a wider destiny, retiring to live in France five years later and dying in Boulogne in 1850.
Pato's army, meanwhile, having been barred from going further by a $5,000 (£3,440) tax on taking horses over the border into Chile, retreated with dignity intact to celebrate with a rest day and a party – tasty goat asado, local champagne chilled in the river and sumptuous chocolate cake.
How to get there
The 11-day Andean Horseback Expedition with Imaginative Traveller (0845 077 8803, imaginative-traveller.com) costs from £1,845 per person, including eight nights' camping, two nights in hotels, land transport, camping equipment, horses, pack mules, local trek leader and guides. Flights available at an extra charge.