Rainbow Valley

Valle del Arcoiris sits in the Cordillera de Domeyko west of San Pedro, where sedimentary beds carry different minerals in successive layers - copper compounds giving green, iron giving red and purple, gypsum and salt giving white - so the hillsides read as bands of colour rather than the uniform brown of the surrounding desert. Unlike most of the Atacama's set pieces the colour is strongest in the middle of the day when the sun is directly on the rock. Nearby at Hierbas Buenas is a rock face with petroglyphs of llamas, hunters and figures, cut by people moving caravans through this route over centuries.

What you actually see

• Bands of green, red and white - minerals in successive beds.
• Colour strongest at midday - unlike most desert viewpoints.
• Hierbas Buenas petroglyphs - llamas and figures on a rock face.
• An old caravan route - the reason the carvings are here.

When to go

Year round, in the middle of the day for the colour. Half a day.

Honest expectations

The colours photograph stronger than they read to the eye - expect subtlety rather than a rainbow. It is a long drive for a short stop. There is no shade or water. Touching the petroglyphs is prohibited and damages them.

Nearby

Hierbas Buenas is on the same route; Calama is west.