Introduction
The Saint-Paul cathedral in Liège is a former collegiate church which was promoted in 1802 to the rank of cathedral, following the disappearance of Saint-Lambert cathedral. The collegiate was probably founded shortly after 965 by the Bishop Eracle. Bishop Notger completed the work and consecrated the church in 972.
The Romanesque church was gradually demolished from the 13th century onwards to make way for the Gothic church. The absence of large-scale excavations has never made it possible to verify them. The reconstruction of the collegiate church began between 1230 and 1240 and progressed from East to West. The chronology of this Gothic reconstruction work is based primarily on the dendrochronology of the building's timbers (Fig. 1) and then confirmed by other arguments (texts, style of carved ornament, etc.).
The objectives of the geophysical prospecting were to discover poss...


