Why was the territory of Roman Bulgaria important as a route between western Europe and the Middle East?

During the Roman era, the territory of modern-day Bulgaria was divided into the provinces of Moesia and Thrace. This region was strategically vital because it was traversed by the primary land route connecting western and central Europe to the Middle East.123

The importance of this territory as a transit corridor was underpinned by the Roman road system, an extensive transportation network built primarily for military and administrative purposes. These roads facilitated the movement of soldiers, official messages, and trade goods across the empire. By serving as a bridge between the European provinces and the eastern reaches of the empire, the region helped integrate diverse communities and supported the circulation of technologies, languages, and cultural practices. The presence of numerous Roman towns and settlements, such as those excavated at Plovdiv, highlights the historical significance of these routes in sustaining the region's connectivity and development.412