The health crisis and its successive confinements were not conducive to exploration. Between two confinements, however, our colleague Matthieu Micoulaut showed us some little-known souterrains in the Yonne and Aube departments, and we were delighted to be able to go back underground; Aube (France), September 2020. [1418N005 © Jérôme et Laurent Triolet/www.mondesouterrain.fr]

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Reference : 1418N005