On day six we expanded the "ecological object" of the Alcoa smelter and looked for the means upon which its operation depends: We drove into the highlands to the Kárahnjúkar dam. Along the way we saw the transmission lines connecting the smelter with Fljótsdal Power Station, we listened to the humming of their transformator station, we saw lake Lagarfljót, whose colour has changed from milky green to milky grey after the dam became operational. Once arrived at the site, we explored the gigantic structure of the dam itself, noticed the marks of wind erosion on the banks of the only partially filled reservoir, and saw the dry canyon where once a river had been flowing freely. The group was stunned by the silence of the place: no sound of flowing water, no birds, and – exceptional for the highlands – no wind on that day.