The Mont Saint Michel— which stands on an island off the coast of Normandy—might be gorgeous whichever way you look at it, but for an abbey this ancient, it has several secrets of its own. A known spot for ghost-hunters who travel from various countries just to glimpse some of its non-living inhabitants, the castle is also a gorgeous feat of architecture.

Why it’s so scary:

During the Hundred Years’ War, Captain Louis d’Estouteville—the commander of the garrison in Mont Saint Michel— led the slaughter of more than 2,000 Englishmen. Legends say that the sand surrounding the castle was bright red with blood.

What to look out for:

Phantom monks, various types of sprectre, and the ghost of d’Estouteville who is said to still be guarding the mount up to this day.