In the Steina valley near Waldshut-Tiengen, a few kilometres north of the Rhine, porphyry has been quarried for more than a hundred years. At first it was cut into paving stones; today it mainly becomes railway ballast, chippings and armour stone.
The reddish porphyry and the grey gneiss are among the hardest rocks in the region. Between 200,000 and 250,000 tonnes are extracted and processed every year. The overburden from the western quarry will later be used to backfill the eastern quarry.
For Eberhard Unternehmungen we photographed and filmed the porphyry works in March 2026, from the air and on the ground: quarry faces, benches, machinery and material.