Next morning we went to Valle Arco Iris (Rainbow Valley) with Flamingo. Very nice tour, small group, less people in the valley, more relaxed and we had a great guide Sophie (we had 2 very good tours with Flamingo and one very bad, see later posts). We stopped at a viewpoint for brief explanation of the geology of Salar de Atacama and Cordillera Domeyko, metal-rich mountain range named after Polish geologist and engineer Ignacy Domeyko.  In Valle Arco Iris we walked around rock formations colored by various metals and minerals (iron, copper, manganese, gypsum, salt). After late breakfast (great French baguettes) we continued to Yerbas Buenas, at the crossroads of ancient Atacameño trade routes, where shamans recorded important events by petroglyphs. Llama domestication is encoded in the drawings. It is all desert now, with just small rivers/streams, but the landscape was created by large rivers flowing through the area some time ago (Rio Grande). In the afternoon we wanted to visit archeology museum, but it was closed for relocation to a larger space, so we just wandered around San Pedro.
