The remains of Roman military caste Dimum are located in the northern part of town of Belene. In the 1st century AD Dimum was a very important point of the Roman province of Moesia. Even during the regime of the first Roman Emperor Augustus the fortress was the most north-eastern point and boundary of the Roman province of Moesia and the Thracian kingdom.
From the beginning of the 2nd until the end of 3rd century here was stationed military horse camp - part of the Roman army, which probably has built the fortress.The site was repeatedly studied by archaeologists. During excavations in 1989 was studied the fortification system of the caste and it was discovered preserved part of it that is long about 60 meters. In 1990 there was found the south tower of the western fortress gate - gate Pretoria. Among the findings are also walls of two buildings (one from the late antiquity and other from an earlier period) and floor of a medieval house.In a castle the archaeologists were found many objects and artifacts dating from different periods - early and late antiquity, early and late Middle Ages, the Ottoman period. Among the finds are a bronze statuette of the goddess Demeter (Isida), bronze ornaments and applications, glass bracelets, home tools and objects, copper coins and more.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.