Romania
There are three valla in Romania, in south-central Dobruja, extending from the Danube to the Black Sea coast. While the relative chronology of the complex is widely accepted, the exact dating of each fortification is currently under dispute. Scholars place their erection at different dates in the Early Mediaeval period, in the second half of the first millennium. In what regards the builders, two theories have gained acceptance, with supporters split, to a large degree, along national lines. Thus, Bulgarian historiography considers the fortifications were built by the First Bulgarian Empire as a defence against the various nomad groups roaming the North-Pontic steppes. On the other hand, several Romanian historians have tried to attribute at least part of the walls to the Byzantine Empire under emperors John I Tzimisces and Basil II, which controlled the region in the second part of the 10th century and throughout the 11th.
The oldest and smallest vallum, the Small Earthen Dyke, is 61 km in length, extending from Cetatea Pătulului on the Danube to Constanţa on the sea coast. Entirely made of earth, it has no defensive constructions built on it, but has a moat on its southern side. This feature has been interpreted as indicating construction by a population living to the north of the earthwork, in order to protect itself from an enemy in the South.
The second vallum, the Large Earthen Dyke, 54 km in length, overlaps the smaller one on some sections. It begins on the Danube, follows the Carasu Valley and ends at Palas, west of Constanţa. Its average height is 3.5 m, and it has moats on both sides. On it are built 63 fortifications: 35 larger (castra), and 28 smaller (castella). The average distance between fortifications is 1 km. The vallum shows signs of reconstruction.
The last vallum to be built, the Stone Dyke, is also made of earth, but has a stone wall on its crest. It has 59 km in length, extending from south of Axiopolis to the Black Sea coast, at a point 75 m south of the little earth wall. The agger is about 1.5 m in height, while the stone wall on top has an average height of 2 m. It has a moat on its northern side and 26 fortifications, the distance between them varying from 1 to 4 km.
The commune Valu lui Traian (formerly Hasancea) is named after the vallum.
Read more about this topic: Trajan's Wall