Mithraeum I. and III. in Hajdina

The area of today’s Municipality of Hajdina has been inhabited throughout all archaeological periods. The oldest finds are stone tools from the Neolithic, while the first settlements date back to the Copper Age. Settlement continued in the Bronze Age, from which burial grounds of the Urnfield culture have been discovered. Graves and burial mounds also remain from the Iron Age, specifically the Hallstatt period (8th–6th century BC).

A settlement with a contemporary burial ground from the Late Iron Age is also known. Around 15 AD, the Romans arrived in this area and built a military camp of the 8th Augustan Legion along the Amber Road. This camp was first mentioned by the Roman historian Tacitus in connection with the election of Vespasian as emperor in 69 AD, and it was supplied with water by an aqueduct of the 13th Twin Legion. In the vicus Fortunae, the commercial and sanctuary quarter of Roman Poetovio, stood the Illyrian customs office and several sanctuaries, including the first and second Mithraeum and the temple of Nutrix. In the Early Christian period, Bishop Victorinus of Ptuj (late 3rd century) served in the local church.

Roman cemeteries stretched along the present-day road toward Pragersko. From the Early Middle Ages, a burial ground was used up until the 10th century. In 1898/99, the First Mithraeum was discovered in Spodnja Hajdina, preserved in situ, meaning at the site of its discovery. It was built in the 2nd century AD by officials of the Illyrian customs office operating in Poetovio.

The sanctuary was dedicated to Mithras, the god of light, who descended to earth to create a new world. The temple is a three-naved structure with a sunken central nave. Within it, monuments were placed, dedicated by worshippers to Mithras himself, to the rock from which he was born, and to his two attendants, the twin deities Cautes and Cautopates, as attested by inscriptions. Among the most important monuments in the First Mithraeum are the statue of Mithras’ birth from the rock and the statue of Mithras dragging the bull across his back – the Transitus.