According to legend the saints rose from their graves in 1039 in order to attend the dedication of Aachen Cathedral. In the background: the church of Saint Servatius in Maastricht.
<bdi><a href="https://en.wikipedia.org/wiki/en:Gaspar_de_Crayer" class="extiw" title="w:en:Gaspar de Crayer"><span title="Flemish painter (1584-1669)">Gaspar de Crayer</span></a>
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R. de la Haye, <i>De bisschoppen van Maastricht</i>. Maastricht, 1985, p. 50, 2011-10-15