Location: downtown Kula


Opening hours: 08:00-17:00 /April-October/

Information: Municipality of Kula Phone: +359 938 32020


The ancient castle Castra Martis was built on a steep southern slope above the gorge of the Voynishka River at the end of the 3rd-beginning of the 4th century as part of the Danube Limes. It occupied a key position in guarding the important Roman road from Bononia to Singidunum (Belgrade).
Castra Martis played an important role in the protection of the border in the 4th- 6th century. It suffered destruction during the Gothic invasions in the late 4th cen­tury and the Huns’ raids in the first half of the 5th century.
The fortress consisted of two parts: a small square fortification (quadriburgium) measuring 40x40 m, with powerful circu­lar towers with a diameter of 12.5 m in the corners and a castle with the shape of an irregular quadrangle. It covered an area of 1.55 ha. The castle was accessible only from the south, where the gate was situated. Probably at the end of the 4th century, the protection of the gate was reinforced by the construction of another narrower wall. Foundations of a Roman bath were discovered northwest.
The quadriburgium is well-preserved and revealed in its entirety. Its fortress walls, built of stone and three-row brick gird­ers, are 2.2 m thick and 2 m tall, and the southeast tower rises to 16.3 m.


According to the Byzantine chronicler Procopius, Castra Martis was one of the fortresses that underwent comprehensive reconstruction during the rule of Justinian the Great /527-565/.