The fortress was created in the middle of the 2nd century AD by the Roman Emperor Antoninus Pius. At the beginning a tower (in Latin "Burg") was built at the swelling. It had locational functions to help boats and small ships entering the lake, and protect them from sinking in the swampy area of the swelling. On top of the tower guiding fire burned at night and in foggy weather.
Foros peninsula was known by more common localizations in the European charts from the 13th-17th century as an old fortress and port under the name Poro (strait) or Poros, which assumes the fortress defended the swelling of Mandra Lake (Skef). A stone inscription from the 2nd century AD (shown in the Archaeological Exposition of Regional Burgas Museum) states that during the Roman Empire at the border of the Roman colony Deultum were built “burgi” (fortifications).
Fortress Burgos / Poros / is the predecessor of modern Burgas. The area also is famous for a certain memorable battle from the time of the Second Bulgarian State. At the beginning of the 14th century the Bulgarian Tsar Theodore Svetoslav made his march to the Black Sea coast, where his power spread over Rusocastro, Mesembria, Anchialos, Sozopolis and Agathopolis. Thus, in 1304 at the bridge over the swelling of Mandra lake also called Skafida (Poros), a crucial battle was held which ended with a significant victory of the legendary Bulgarian ruler over the Byzantine army.
Transport accessibility: Access through E87 - main road direction Sozopol - Burgas. The fortress could be reached by car, there are parking lots.