Dating between 800 and 1,000 CE, about 170 Viking swords have been discovered all with the inscription “Ulfberht” on them. The mysterious thing about them is the incredible craftsmanship for their time and their rarity. Archaeologists are baffled by the purity of the metal that they thought couldn’t be done until the Industrial Revolution. With how strong, rare, and powerful the swords were, many believe they could have been considered “mythical” at the time and used by the most elite Vikings.