A fortlet with a heating system, which caught fire.

Near Logatec, on the southern ancient connection between Vrhnika (Nauportus) and Ajdovščina (Castra), which extended through today’s Razdrto near Postojna (Ocra), a barrier line with a fortlet and three quadrilateral towers can be found. On the hilly terrain of the Logatec Plateau, near the Brst Hill, with its 604 m in length, the barrier used to close a narrow passage with a Roman road.

The Brst near Martinj Hrib barrier extends in the direction from the southwest to the northeast. In the middle, where the line is concave, a smaller multi-angle fortlet is incorporated in the barrier, from which good control of the entire barrier is possible. In it archaeologists excavated a building with a hypocaust – a Roman floor and wall heating system. This suggests that a military crew might have been stationed there throughout the year, even during the cold winter months. A distinctive feature of the barrier is one of the towers located on its outer (north-western) side (the other two towers are on the inner side). It seems this is a distinctive element due to the adaptation to the terrain, since it is placed on a smaller natural pier.

In comparison with other barriers of the claustra Alpium Iuliarum system, the small finds in Brst near Martinj Hrib are somewhat more numerous. Among them, coins, iron attack weapons (spear points) and other parts of military equipment, such as fibulae (brooches) are very common. Narrower dating of the finds and their concentration place the formation of the barrier into the second half of the 3rd century. A bunch of nearly 200 coins glued together is evidence of a fire and the abandonment of the barrier at the end of the 4th century.