World's Most Mysterious Buildings
John Woods / Alamy
Church of St. Mary Magdalene, Rennes-le-Château, France
The mystery of this church in southeastern France reaches far beyond Dan Brown novels. Bérenger Saunière, a priest in the village of Rennes-le-Château in the early 1900s, is believed to have discovered the treasure of the Cathars, a Christian sect founded in the 11th century, inside this clue-laden house of worship. The cache of gold is rumored to have been stolen from the Temple of Jerusalem by the Romans in A.D. 70—and possibly connected to the legends surrounding the super-secret Priory of Sion, Knights Templar, Holy Grail, and the real tomb of Jesus.