100 kilometers north of Nantes, near Retiers in the small commune of Essé, the more adventurous will encounter the Idyllic Roche Aux Fées, or “fairies Rock.” The site has been known for centuries but only recently made more presentable. Within the last couple of decades, the local commune, encouraged by the local priest, cleared the area and bought up a bankrupt local golf course to build a parking lot and small visitors center. There is an enthusiastic attendant there. 

In its original state, Roche Des Fées, would have been a south east facing nearly 20 meter long barrow, with several large chambers. It is constructed with very large, nearly rectangular reddish brown basaltic blocks that give the site a very structured look. As it stands, it could be described as a mini Stonehenge, were it not for its roofed rectangular shape. It is said to be one of the largest sites in Europe. Originally, it would have been covered by a tumulus, which is now long gone. A couple of the medium sized stones are also displaced to the sides, a 300 year old oak growing over one of them. One of the roof slabs lost a small chunk due to degradation of the rock over 5,000 years, and this piece now lies on the floor of the middle chamber. 

Roche Aux Fées served more as a grave, but rituals took place here, according to my pendulum. The cap stone at the entrance has a few indentations, in which blood traces have been found, which would have resulted from animal sacrifices. The South/East facing entrance points directly towards the winter solstice sunrise. The blocks were originally quarried 4 km away, according to the guidebook. 

Source:http://www.megalithic.co.uk/article.php?sid=1511