Kameni vrh - Gaveznica

Gaveznica – Kameni vrh is a protected geological monument on the edge of Lepoglava, in Croatia's Zagorje region, tucked less than half a kilometer from St. Mary's Church. The site is unusual on two counts: it is Croatia's only preserved trace of an extinct volcano, and the only known deposit of a semi-precious stone in the country — the so-called Lepoglava agate.

What will you see there?

The hill is built from andesite, volcanic breccia and tuff, rock formed by volcanic activity dating back roughly 22 million years. Over millions of years, successive seas that covered and retreated from this part of Central Europe wore away the original volcanic cone, leaving behind the jagged rock formations visible today. The former summit, once 373 meters high, is now a wide depression left by the abandoned quarry, its shape still echoing that of a volcanic crater.

The quarry's history

For almost half a century, from 1923 to 1967, the quarry was worked by prisoners from the nearby Lepoglava penitentiary. They extracted hypersthene andesite, an exceptionally hard rock used for road surfaces and foundations. It was during this quarrying that veins of semi-precious stone were discovered — agate, opal and chalcedony — formed in the final stage of volcanic activity through hydrothermal effects on the surrounding rock.

Traces of earlier settlers

Gaveznica – Kameni vrh is not only a geological rarity but also an archaeological site. Remains of a settlement from the Late Bronze Age have been found on the former hilltop, showing that people were drawn to this striking spot long before quarrying ever began.

How to get there and when to visit?

The site sits right at the edge of Lepoglava, within walking distance of St. Mary's Church, making it easy to combine with a visit to the town and its monastery. The best time to explore is spring, summer or early autumn, when the rock exposures are clearly visible and the paths are dry and easy to walk. The area has held protected natural monument status since March 18, 1998, as the sixth such site in Croatia, so collecting stones or disturbing the terrain is prohibited.

What should you know before visiting?

Regional authorities are planning a visitor center for Gaveznica – Kameni vrh, which should eventually make the site easier to explore and better explained on location. For now, sturdy footwear is recommended, since the former quarry ground is uneven and paths run alongside rock walls.

Frequently asked questions

What exactly is Gaveznica – Kameni vrh? It is a geological natural monument in Lepoglava — the remnant of an extinct volcano active around 22 million years ago, and Croatia's only known source of agate.

Can visitors collect stones there? No. The site has been legally protected since 1998 as a natural monument, so removing rocks or minerals is not allowed.

How long was the quarry in operation? The quarry operated from 1923 to 1967, worked by prisoners from the Lepoglava penitentiary.

Are there other attractions nearby? Yes — Gaveznica – Kameni vrh is very close to the center of Lepoglava, with its monastery and St. Mary's Church, so both can easily be visited on the same walk.