Even then the Amarok keeps going; the problem is our lax approach to loading. On side slopes, the posts all try to roll downhill, piling up against one side of the load bay and bringing the truck even closer to tipping over; and when we go straight up, they try to slide straight out the back. We stop every few dozen yards to drop off a few more; but when Alastair gets hard on the gas to bounce over a particularly big tuft, the Amarok rears up and the remaining half ton goes shooting out the back.It's only by jumping up that Diego and I avoid getting dumped out with it. Diego bangs on the roof to tell Alastair we've gone as far as we can. We don't bother putting it back on; the fencers can shift it by hand.

Inside Alastair is wiping the sweat from his face. "Man, that was a test." He seems genuinely impressed. "I could never could've done that in the Ford. I was going to have to bring that timber up here by horse. I don't think 99.9 percent of the people who buy this thing will ever do anything like that. Just don't tell the blokes who own it what you did in it." I don't think we can hide it; the back is full of sheep dung, we've cracked a taillamp, torn off a mud flap, and have a punctured tire.

Back at the ranch, we have a traditional Argentine asado barbeque, in which vast flanks of cattle are scorched over open flame until they're nut-brown and taste beefier than anything else you'll ever put in your mouth. Argentinians eat an average of 161 pounds of cow each year, almost twice as much even as the Americans, and the previous El Presidente nearly got himself impeached when he suggested they should cut back.

Alastair and Roger ask us where we plan to go next. We tell them we're planning a long loop through the steppe, using two of Argentina's most famous roads: the Ruta 40, which will take you from one end of this seemingly endless country to the other, if you have a spare month, and the Ruta 23, an almost entirely unmade road that runs from here near the Chilean border all the way east to the ocean.

Along the way we'll pass through a couple remote gaucho towns seldom visited by outsiders. Roger knows one of them. "Ha! That's where I found those Land Rover parts. I haven't been there in decades. You should see if that general store is still there. You'll love it. It's the kind of place that has a brassiere hanging up next to a camshaft."

Alastair isn't so sure. "It's the Wild West out there. If they don't like you, they'll just stab you."

Patagonia seems to feature on every serious traveler's list of places to see before he dies. Road-trip across it, and your average speed will be dented by the constant need to stop and take pictures. Where there is a paved road, it runs arrow-straight over the vast, flat glacial valley floors, the twin yellow central lines converging at a vanishing point in the far, far distance. Bare, brown hills rise sharply at the edge of the flat steppe, and beyond them are snow-covered volcanic peaks of the Pacific Ring of Fire. There are long, glacial lakes whipped into 10-foot swells by the fierce winds, iron and copper deposits that stain the mountainsides red and blue, and condors and turkey vultures circling against weird cloud formations unlike any I've seen before.