On Friday and Saturday evenings in the summer half of the year: Bach and Vivaldi inside the cathedral, played by the Harmonia Ensemble Wien. Sixty minutes, no interval. The concerts support the cathedral, and that is not a footnote, it is the reason they exist.

This is the most transparent organiser in the whole field: works with catalogue numbers, soloists named, clear prices. Later in the year come the Mozart Requiem at the hour of his death on 4 December and the Advent concerts. Tickets at kunstkultur.com.