MOHOVO, CROATIA—Archaeologists have unearthed a watchtower on the Danube along the Roman Empire's northern border, Live Science reports. The 130- by 100-foot structure was built in the late second century a.d. during the reign of the emperor Marcus Aurelius. This was the period of the Marcomannic Wars (circa a.d. 166–180), when the Romans were defending the border from incursions by the Germanic Marcomanni, who inhabited the area north of the Danube, and the nomadic Sarmatians. "The watchtower was built in a strategic location, at one of the crossings over the Danube River," said archaeologist Marko Dizdar of the Institute of Archaeology, who leads excavations at the site. "From this position, there was excellent visual control of a large area, and it was also naturally protected on three sides by deep natural ravines." Defensive ditches and a wooden palisade surrounded a wooden building at the tower's center. Dizdar and his team recovered fibulas, pottery, iron arrows, and other artifacts that indicate the tower continued to operate throughout the third century a.d. In the fourth century, threats from Germanic tribes necessitated an increase in the Roman military presence in the region. At this time, Dizdar said, the soldiers stationed there likely built a fort that replaced the watchtower. The team will continue excavations at the site with the aim of exploring this shift. To read about archaeology along Hadrian's Wall on another of the empire's borders, go to "The Wall at the End of the Empire."
