Archaeologists are informed about the course of the planned route, even before construction work begins, so as to be able to respond quickly in case of any findings.
They document all previous findings in the area concerned. Areas of archaeological interests include a zone in Hernals, where there were many workshops during Roman times.
Archaeological findings in Vienna are generally no more than four metres below the surface, which is why care usually needs to be taken when building stations, but not when tunnelling deeper underground.