Dunaalmási Kőfejtő Természetvédelmi Terület

The Dunaalmás Quarry Nature Reserve is located on the border of the settlements Dunaalmás and Szomód, in the northern part of Komárom-Esztergom County, at the northern spurs of the Gerecse. The area covers approximately 230 hectares. The quarry falls under the jurisdiction of the Directorate of the Danube–Ipoly National Park. The Dunaalmás‑Szomód tourist trail and the Dunaszentmiklós‑Kőpite‑hegy tourist trail both pass through it.

The quarry was already operating in Roman times, when material was mined here for the nearby fortress of Brigetio. The stone barrel road, the Roman Road, which is a monument, is the longest surviving Roman‑origin road in Hungary. The quarry operated until the time of the Second World War.

The Pleistocene‑age fossil material includes, among others, an individual of an ancient elephant species (Elephas planifrons), individuals of an extinct turtle species (Clemys méhelyi) and remains of freshwater crayfish.

A pine forest was planted on the former steppe sand meadow. Of the approximately 33 fern species occurring in Hungary, 18 live here, on an extremely small area, representing a unique species richness.

Brief description of the protected natural area

As a construction material, the source limestone was already utilized by the Romans, and its mining continued until the Second World War.

The Gerecse is a characteristic faulted mountain range. Along the fault lines bordering the mountain mass (primarily along the Tata and Danube valley fault systems) abundant spring water sources emerged, and from these the spring limestone was formed. Above Dunaalmás the extent of the spring limestone exceeds 2.5 square kilometres, with a thickness of 20–25 metres. The extraction of the spring limestone began in the Pannonian period and in places lasted almost to the present day. The complete cessation of spring activity occurred as a result of the severe lowering of the karst water level associated with mining in the Tatabánya coal basin.

The rock material of the protected quarry series was deposited in the lower Pleistocene. The quarry series essentially consists of the former four large mines. The Dunaalmás spring limestone is of the so‑called tetaratic development: the springs from which the spring limestone was extracted extended in a north‑westward direction. Dams 3.5 metres high were built from the spring limestone. Water passed through these, collecting in shallow lakes 30–50 m in diameter.

Extremely valuable paleontological material was discovered in the quarry area. An interesting part of the material includes an ancient elephant species (Elephas planifrons), an extinct turtle species described here (Clemys méhelyi), and freshwater crayfish that lived in the spring lakes.

Equally interesting and rare is the plant community living on the surface of the protected quarries: a pine forest planted in place of the steppe sand grassland and the Somogy fern forest (providing refuge for 18 of the 33 fern species occurring in our country). Such a habitat, where so many fern species, as well as their hybrids and varieties, occurred in such a small area, was not known anywhere in Europe. Unfortunately, the climate/weather changes of recent decades do not favor the preservation of the habitat.