Le Chene Chapelle: The Ancient Oak Tree Chapel as Old As France Itself
I will tell you where they are. …, they are already in their home under the ground, a very delightful residence of which we shall see a good deal presently. But how have they reached it? for there is no entrance to be seen, not so much as a large stone, which if rolled away, would disclose the mouth of a cave.
Source: ancient-origins.net