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In page Vulcano:

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Vulcano is also mentioned in the pilgrimage report (ca. 1350) by Ludolf von Sudheim, who, however, claims that he did not dare to climb it. Unlike Burchard of Mount Sion, Ludolf expected to find the entrance to hell at the crater. The Provençal knight Antoine de La Sale tells of an excursion to the island in 1406. His text is a didactic textbook for his pupil John of Calabria, the son of Duke Rene I of Anjou.[citation needed]