AARHUS, DENMARK—Radiocarbon dating of logs from the ring fortress that was unearthed in Denmark earlier this year confirm that it dates to the Viking period, sometime around the tenth century, meaning that it could have been built during the reign of King Harald Bluetooth. "We can’t say whether or not it’s Harald Bluetooth’s fortress yet, but now that we’ve dated it to the tenth century, the trail is getting hotter," medieval archaeologist Søren Sindbæk told Aarhus University News. "The things we’ve discovered about the fortress during the excavations all point in the same direction. We already know that there’s a good chance that we’ll find conclusive evidence next year.” Sindbæk notes that Harald Bluetooth oversaw the construction of three known fortresses in Denmark, and that their dimensions and the structure of their ramparts and gates are very similar to those of the newly discovered stronghold. "It’s hard to avoid the sense that the same master builder was responsible,” says Sindbæk. To read more about this era in Scandinavian history, see "The First Vikings."