Konstanz sits where Lake Constance narrows into the Rhine, and for four years in the fifteenth century it hosted the Council that ended the Great Western Schism, healing a papacy that had split three ways. The city has been needling that history ever since: a nine-metre concrete courtesan rotates at the harbour mouth, holding up small caricatures of a pope and an emperor. This self-guided walking tour follows that streak of civic irreverence through eight stops in the old town, from the medieval Rhine gate tower to the Council Building where a pope was elected. Everything runs from your smartphone, with no app to install and no physical guide to keep up with. You get a map of all eight stops, walking directions through Google Maps, and a short audio storey with an interactive quiz at each location. Walk at your own pace, stop for a coffee by the lake whenever you like, and pick the route back up when you are ready.