There is an early start for today's long and spectacular journey up through the Andes and into Chile. Upon leaving Salta the bus passes through dense vegetation, palms and bromeliads, before ascending into a mountainous valley with a kaleidoscope of coloured rock faces. A series of hairpin bends then take you into the clouds, and the foliage peters out and is replaced by an arid landscape of cacti and brush.
Soon the parched salt flats of the Salar Grande reveal themselves as you near the international border, a remote outpost at 4,900m, and from here you descend into Chile, passing multi-coloured lagoons which reflect the perfect conical peaks of volcanoes dusted with snow. As you swoop down into the Atacama desert you see a distant patch of vivid green, the oasis of San Pedro, your base for the coming nights. This is a 10hr journey, including stops.
San Pedro is an adobe town somewhat lost in time, with a laid back atmosphere and an erratic electricity supply. Its dusty streets are lined with bars, cafés and tour operator offices offering various kinds of excursions into the surrounding desert. The excellent museum here has a comprehensive history of the local indigenous population and an interesting display of local archaeological discoveries.