To protect the borders of Danubian Bulgaria, Khan Asparuh launched a large-scale construction effort. It was aimed at building a series of earth mounds and trenches that stretched for dozens of kilometers. Some of these defenses were reinforced at strategic points with additional fortifications - initially made of wood and later of masonry, becoming part of the so-called auls or forts that guarded the borders.
Along the Black Sea coast from Varna to the south, the Proto-Bulgarians fortified all the coastal areas where the Byzantine fleet could land. Directly on the shoreline or on the first accessible field above it, they built a high embankment, including a trench facing the sea. The site of Asparuhov Val at the bottom of Varna Bay is one of such defensive ramparts. Initially, the structure was more than three kilometers long. An anterior marble column with IYI (a Proto-Bulgarian ssymbol) was found there. Fortified camps were also built on the high shore above the Bay of Kavarna.
In the lowest central part of Dobrudja, where the Danube is closest to the sea at Constanta and through the fields and hills, the country is crossed by three mounds. Two of them - the small earth trench and the large earth trench, differ in the size of their embankment. The third - the so-called stone mound, is lined on the frontal north face with stone (limestone), carved in regular blocks.
Initially, the great trench was facing north. According to some researchers, its construction dates back to the late Antiquity – between the IVth and Vth centuries. It is believed that the reason for the strengthening of this narrow part of Scythia Minor was the threat of the Goths or Huns. Some researchers more recently pointed out that in fact the mound was built against the Bulgarians, who were once part of the Hunnic tribal alliance and fought under the leadership of Attila and his sons. There is a wide ditch in front of the northern face of the trench, which makes it difficult to cross from the north. On the inner side of the trench, i.e on the southern side, towards the earthen embankment, there were large earthen fortifications - camps, where the army was stationed to defend it.
After the Proto-Bulgarians settled in the northern part of Scythia Minor, they turned the face of the trench towards the south, digging a new ditch on its southern side, crossing the mounds of the large camps. This reconstruction of the great mound took place simultaneously with the rapid construction of the great camp at Nikulitsel, where it is believed that the original capital of Danubian Bulgaria was located in the area of Ongal.
In popular culture, the memory of construction and fortification works of Asparuh in this part of Dobrudja was preserved until the end of the XIth century, which shows the extremely important role played by the ramparts and earthen fortifications in the First Bulgarian State.
The Stone promontory can also be linked to the protective facilities erected by the founder of the Bulgarian state. It also faces north. The stone promontory is an earthen structure, similar to the others, but its face is lined with carved limestone blocks. A moat passes in front of it, which, like the others, makes it more inaccessible. The straight carved blocks, which gave it a very monumental appearance, are undoubtedly an analogy with the construction of large stone buildings in the central cradle of the Proto-Bulgarians - Pliska.
The mountain passes in the Balkan range were a reliable protection for the Bulgarian state from the south. Although the Proto-Bulgarians have long been familiar with the Byzantine cities, population and culture, and the Slavs had lived for eons on Byzantine territory, the recent entry of the Proto-Bulgarians into the Byzantine land created constant conditions of mistrust and conflict between those who were true masters of the Lower Danube provinces and those who felt like its rightful owners. Both the Bulgarian rulers and the Byzantine emperors made efforts to strengthen the accessible roads of the passes and gorges in the Balkan Mountains. Such a barrier, several tens of kilometers long, stretches from the Black Sea coast at Obzor (the medieval town of Kozyak) into the mountains. It is in some places still an impressive earthen structure and is known by its more recent Turkish name “germe”.
The issue of protection against the Avars was too serious for the young state. Although the Avars were a people close in origin and culture to the Proto-Bulgarians, they were a fierce adversary. A long earthen protective belt was erected throughout Wallachia. Its two ends rested on the Danube. Among the local Romanian population, it is called Novakova Brazda.
The western parts of the country reached somewhere near Lom. The territory of the famous seven Slavic tribes stretched up to this point. Behind these trenches, the Slavic and Proto-Bulgarian elite warriors stood side by side.
The system of protective ramparts, earthen fortifications and protected border settlements and military camps, which Khan Asparukh erected with his Bulgarians and Slavic allies, became a serious obstacle to their foes. Thanks to them, the inhabitants of Danubian Bulgaria managed to repel the invasions of the Byzantines, Avars and to resist the attempts of the Khazars advancing from the east in a fury of screaming arrows and clashing sword blades.
Subsequently, after repelling the initial incursions, this system of defensive fortifications and guard posts developed and improved.
At the Historical Park, visitors can see the reconstruction of a Proto-Bulgarian fortified military camp, typical of the time of Khan Asparukh and the protective system of ramparts. The facility is surrounded by a moat, has a raised embankment of earth and pointed stakes, where warriors can be stationed in portable yurts or in wooden houses. Such fortified settlements were an integral part of the system of ramparts with which our ancestors defended their land.
Visit the Historical Park, become part of the history of the great Bulgarian people.