The »Indulgentiae ecclesiarum urbis Romae« was the most important guide for late medieval pilgrims to Rome. It describes Rome's seven main churches (and selected others), making special reference to indulgences and relics but also touching on the history of these churches and their architecture (e.g. the number and style of altars and chapels). The present volume is a critical edition of the major German and Dutch versions of the text. The commentaries examine the »Indulgentiae« for the light it casts on questions pertaining to the history of religious piety (obtaining indulgences, veneration of relics, 'pilgrimages in spirit').