During work in the zoological garden of the citadel of Besançon, the workers discovered two corridors and an underground room. But this place was completely unknown, not appearing on any current plan.
A hole in the zoological garden
The citadel of Besançon is a stronghold overlooking the city of Besançon (Doubs), built by Sébastien Le Prestre de Vauban, military engineer to King Louis XIV. Its construction began in 1668 and was completed in 1683. The citadel is on the list of Unesco World Heritage since 2008, among the twelve Fortifications of Vauban.
The official Facebook page of the site posted a photo on March 25, 2021, recounting an astonishing discovery. It is about an unsuspected space not appearing on any current plan, namely two corridors and a room. The fact is that this monument has already been explored and studied many times. Thus, this new place had thus gone completely unnoticed.
The staff first noticed a hole near the zoological garden where work was taking place. However, the diameter of this hole, as large as that of a manhole, seemed to increase. Alerted, the city’s historical heritage experts then carried out a verification.
A room possibly abandoned in the 19th century
The experts inserted a camera in this hole in order to obtain a 360 ° view of what was inside. The surprise was great when a vaulted space pierced with shooting windows and corridors appeared in the images. In total, there were two corridors about fifteen meters long and above all, a 13 m long by 1.50 m wide and 2 m high. The room was empty and the shooting windows were blocked. For the moment, the investigation does not yet allow to know how far the corridors lead.
“It was undoubtedly created around 1835 and was abandoned at the end of the 19th century when defense needs were less significant”, said Marie-Laure Bassi, director of historical heritage of Besançon in an article by Eastern Republican of March 26, 2021.
Nineteenth-century plans mentioned this room possibly serving to defend one of the ditches on the relief front of the citadel. However, no one had carried out checks before today. At the moment, the experts perform a health diagnosis in order to check the condition of the walls. Only then will it be a question of seeking to define precisely the vocation and the functioning of this place.