Borshi valley is another crossing road linking the coast with the main land, where four fortifications were discovered. The fortress of Sopoti, where the acropolis of the ancient town of Borshi is located, has the perfect natural protection, which has conditioned the establishment of a prehistoric fortification.
The prehistoric wall is preserved near the Acropolis and the entrance to the medieval castle. It was built with the same construction technique as the settlement of Karos Phase I. The prehistoric wall was supported by a residential pottery horizon dating back to the late Bronze Age. A settlement was also found outside the prehistoric wall, which is associated with a dwelling of fortification time. The ceramics found in residential horizons, clay, forms and invoices, is similar to that of Badhra. From the forms of dishes are distinguished, a spherical body with S-shaped profile, with scattered edge, similar to those found in Badhra. Spherical pots, with straight or sloping edges, similar to those of Badhra.
The fortress of Sopoti dates back to the late Bronze Age. The castle was heavily damaged during the barbarian invasions of the fifth and sixth centuries A.D., and it was rebuilt in the Middle Ages at which time it took the name of Sopoti Castle. In 1417 the castle was seized by the Ottomans who later restored it in the 18th century.