"El esta borracho!" The mother with two children screamed as the drunken bus driver wove between imaginary traffic cones at 70km an hour. We were only 500m down the Route 40 and already it seemed as if our trip might be prematurely cut short by a passenger revolt or worse an overturned bus tossing us around in a tumble drier of rucksacks and contraband. It wasn't even meant to be like this. We had intended hitching the legendary road from Bolivia to Tierra del Fuego as far as Mendoza. Yet three hours in the punishing sun by the road in the border town of La Quiaca soon changed our minds. There was no traffic and the little shade provided by a small pathetic tree soon evaporated as the sun got higher. We were grateful when we saw that bus meandering up the highway but now we weren't so sure.

Not to be deterred from our original intentions, we got off in the first big town and started hitching. There was more traffic now but nobody was stopping, all signalling they were turning to some mysterious place left. Eventually a little car whizzed by and ground to a halt -our first lift in Argentina. He was German and she was a Portena, on holiday from Europe with their two shy kids. The young couple looked puzzled when we told them our plan. This isn't the route 40 they said. We'd missed the turn further back. Oops.

Nevermind, we would still see Quebrada de Humahuaca. Our lively conversation became peppered with words such as "Wow!" "Look at that!" "My God!" Until eventually we were lulled into silence, gobsmacked by the beauty of such colourful mountains. The landscape appeared as rainbows made of stone.

As the truck hurtled downhill through misty valleys the air became more sticky and humid and the landscape greener. Suddenly everything was tropical. The unpronounceable city of Jujuy appeared, nestled in a verdant valley, modern and prosperous looking. We tried to get the driver's attention to drop us off on the road heading south but he ignored us and turned off and tore down through the city instead. The town centre whistled by in a blaze of colour and next we were rising again into leafy suburbia. Where's he taking us? Eventually he pulled up in front of a mansion.

It was dark by the time we got to Salta. We caught a taxi to the campsite and fumbled around in the dark to pitch our tent. We couldn't believe our eyes the next morning. Before us was a huge, blue, shimmering swimming pool the size of a lake. One of the biggest in the world seemingly. It takes a week to fill, our camper van neighbours told us. The campsite itself was big and busy with a holiday atmosphere. The weather was gloriously sunny. We weren't going anywhere. 

Two days later we're hurtling through tobacco country in the back of another pick up south of Salta. We were crammed in with three Argentine hitchers but we didn't mind. This is the best way to see Argentina - loud and airy, screaming as opposed to talking. Quebrada de Cafayate unfolded before us like a pop up picture book, a red canyon with weird and wonderful rock formations.

The Route 40 continues south to Chilecitos. We're in the back of yet another pick up with a family sitting up front. They passed us drinks and snacks and then signalled they were turning left towards Tafi de Valle. We went with the flow and decided to tag along. So long for now Route 40. The road ascended dramatically, zig zagging through the 3050 metres high Abra del Infiernillo (Little Hell Pass). Within minutes the weather transformed from scorching heat into misty cold. We were driving through cloud. Suddenly it started to rain. The driver stopped and covered the back with tarpaulin, with just our two heads jutting up.