Rupnica

Rupnica is a geological nature reserve near Voćin featuring columnar rock formations created by ancient volcanic activity. The exposed rocks display clear hexagonal and square patterns, forming a striking natural arrangement of geometric shapes.

The site was recognized in 1948 as Croatia's first geological monument, protecting evidence of volcanic activity from the Cretaceous period. This official status helped ensure the geological features remained preserved for future study.

The reserve functions as a place where visitors learn how ancient volcanic forces shaped the land they see today. People come here to explore how rock formations develop and to understand geological processes firsthand.

The site offers marked hiking paths and information panels throughout, making it straightforward to explore the rock formations. An on-site Geo Info Centre provides additional context to help visitors understand what they are observing.

The columnar formations developed through a remarkable natural process where cooling lava fractured into nearly perfect geometric patterns. The regularity of these shapes is so precise that they almost appear human-made, yet they formed entirely through physical forces.