The abbey of Orval, in Belgium's Ardennes Forest, is truly a place of mystery. The name "Orval" means "Valley of Gold", Nostradamus seems to have written a number of his prophecies here, and it is possible that once there were no less than two treasures hidden: the Treasure of the Knights Templar and the War Chest of Louis XVI and Marie Antoinette...

In the international bestseller The Holy Blood and the Holy Grail (Michael Baigent, Richard Leigh & Henry Lincoln) we are told that in 1070, 29 years before the First Crusade, some monks from Calabria, southern Italy, arrived in the Ardennes Forest that belonged to Geoffrey of Bouillon. The monks were led by and individual named Ursus, who - according to the so-called "Priory Documents" - was consistently associated with the Merovingian bloodline, or in other words: with the descendants of Jesus Christ.

The monks were welcomed by Count Arnould of Chiny and by Geoffrey's aunt and foster-mother Mathilde of Tuscany, Duchess of Lorraine. From Mathilde they received the land that is now known as Orval, not far from Stenay, where once King Dagobert II was assassinated. Before these monks settled in Orval, there wasn't any human habitation, although there were some Merovingian tombs discovered near the well.

A well-known legend says that the monastery was born out of gratitude. Mathilde, a widow, had lost her golden wedding ring, which was accidentally fallen into the fountain. She prayed to the Lord and suddenly a trout rose out of the waterwith the precious ring in its mouth. "Truly," Mathilde exclaimed, "this place is a Val d'Or, a Valley of Gold!" - You still can visit this well, where she established a monastery.

Full story here:
http://www.socyberty.com/History/Mysteries-of-the-Valley-of-Gold-Orval.647381/1