Archaeological research at the site began in 1986 and continues nowadays. Her research began pioneers of Bulgarian archeology Constantine Irechek and Shkorpil brothers. The remains of architectural buildings testify to the existence of a major medieval monument. Initially, in the V century was built an unique early Christian martirium, which is unprecedented in the Balkans. Firstly it is multilayered Christian religious complex, located in the highest part of the hill in the central part of the fortress.
Another significant discovery, representing construction masterpiece is the water supply facility – a complex building system, towers, water tanks and tunnel connecting the fort to the river. The archaeological studies are found not only architectural remains, but many arrows, coins, stamps, jewelry, unique ceramics. Hence, the most numerous artefacts from the period of the First Bulgarian Empire from across northeastern Thrace.