The GSSP proposal to formalize the base of the Campanian Stage at a point indicated by the magnetic polarity reversal from Chron 34n (top of the Long Cretaceous Normal Polarity-Chron) to Chron C33r at 221.53 m in the Bottaccione Gorge section (Gubbio, Umbria-Marche Basin) in Italy was unanimously approved by the IUGS Executive Committee in October 2022.