Great, a treasure! Well, I’m going to tell you about St-Bruno's treasure: they said that few monks, forced to run away during the Revolution, hide a treasure in some mysterious undergrounds! In middle of the 19th century, people came from all the country in order to seek the treasure.
They started to dig every night... they finally found the underground’s exit above Notre-Dame church, which led to a burial room in Saint-Bruno! A vault which gave you the willies, but which wasn’t desecrated during the Revolution, contrary to Sourdis' grave. Inside this vault, surprise!
They found dry corpses, wearing white clothes... bodies of Carthusian monks who took shelter here in order to escape from the revolutionaries: they probably died, starving, in their hiding place! But in contact with the air, the corpses crumbled into dust... and people never found treasure, of course.