The Cerro de los Siete Colores, the Hill of Seven Colours, is a hillside above the adobe village of Purmamarca in the Quebrada de Humahuaca, in Jujuy province of northwestern Argentina, striped from green to red and violet by 600 million years of seabed and desert stood on end, and it is walked around on a loop behind the village, looked at from a lookout above the roofs and photographed from the plaza market with the striped ridge filling the sky. The colours are layers of rock laid down as marine sediment, lake bed and desert over hundreds of millions of years and tilted upright by the rise of the Andes, each mineral giving its band, iron for the reds, copper for the greens, at their sharpest in the first light of morning; the Paseo de los Colorados loops for an hour behind the seven-coloured face, where the famous bands drop out of sight and the rock settles into one deep red cut into ridges and hollows, and three blocks from the plaza a short steep path lifts the visitor to the El Porito lookout above the adobe roofs, with the whole ridge lined up behind the village.
Purmamarca is the village at the foot of the hill, a grid of adobe around a plaza where stalls hung with llama and sheep wool, ceramics and carvings of cardón wood crowd the square every day of the week. The Iglesia de Santa Rosa de Lima of 1648 is raw adobe under a roof of cardón, the candelabra cactus that grows so slowly that a ten-metre plant has stood for 180 years, and the carob tree beside it is reckoned more than 650 years old. The village opens its carnival by digging a small devil out of a cairn on the hillside, and for the eight days he is above ground the rules are suspended. The Cerro de los Siete Colores is the Earth's layers turned on their side, and the village lives at the bottom of the page.