Source of the river Coquille

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The river Coquille is a tributary to the great river Seine, which runs through Paris. In ancient times, this source was an important religious assembly place. People came here in Celtic times, long before Julius Cesar conquered Gaul, to make offerings to a feared goddess. This goddess was reputed to take away small children - especially in the spring time when waters ran high.
The area around the source is excavated by water in such a way that it appears as a large, mysterious theater where spirits assemble.