Apolena

Apolena is a nature reserve and sandstone rock city located roughly 400 meters east of the village of Troskovice, in the Semily district of the Liberec region in the Czech Republic. The reserve protects a forest ecosystem growing across a rock city and forms part of the Bohemian Paradise (Český ráj) Geopark, which in 2015 became the first Czech geopark to join the UNESCO Global Geoparks Network.

How did the Apolena rock city form?

The rocks of Apolena are built from unusually soft sandstone containing a small admixture of kaolinite cement. This composition made the fractured sandstone plateau exceptionally vulnerable to erosion. The shape of the terrain was influenced both by the eruption of the nearby Trosky volcano, active around 17 million years ago, and by the gradual subsidence of individual rock blocks along the slope of the Libuň trough (Libuňský příkop). The combined effect of volcanic activity and slow ground movement produced the reserve's distinctive massif of isolated towers and turrets carved from soft rock.

What lies beneath the surface?

Beneath Apolena's rock formations lies the largest system of fissure-type caves in the whole of Bohemian Paradise. One of them, the Sklepy cave, serves as a winter shelter for bats. The site holds European significance as a habitat for Alcathoe's bat (Myotis alcathoe), a critically endangered species. The narrow fissures and underground passages create a stable microclimate that allows bats to hibernate safely, sheltered from the temperature swings of the surface.

What wildlife lives here?

Beyond its bat population, the rock walls and towers of Apolena provide favorable nesting conditions for cliff-dwelling birds. The reserve is home to the common kestrel, the eagle owl, and the jackdaw, species that rely on ledges and crevices inaccessible to ground predators to raise their young safely.

Can visitors enter the Apolena reserve?

The Apolena nature reserve was formally established in spring 1998, but a complete access ban to the rock city has been in place since spring 2010. The closure was introduced because of ongoing damage to the fragile, soft sandstone caused by visitors climbing on and walking across the rock surfaces. Today Apolena functions as a strictly protected reserve whose primary purpose is safeguarding its unique forest-and-rock ecosystem and the habitats of its threatened species, rather than accommodating tourist traffic.

Frequently asked questions

Where exactly is Apolena located? The reserve lies about 400 meters east of Troskovice, in the Semily district of the Liberec region, within the boundaries of the Bohemian Paradise Geopark.

Can you hike into the Apolena rock city? No. Since spring 2010 the rock city has been completely closed to visitors in order to protect its fragile sandstone formations from further erosion and damage.

Why is the sandstone at Apolena so fragile? The sandstone that makes up the rock city contains a small amount of kaolinite cement, which leaves it unusually soft and highly susceptible to erosion and mechanical damage.

What species does the reserve protect? Most notably the critically endangered Alcathoe's bat, for which the Sklepy cave is a habitat of European importance, as well as cliff-nesting birds such as the common kestrel, eagle owl, and jackdaw.

What is the Bohemian Paradise Geopark? It is a protected area covering the Český ráj region, which in 2015 became the first Czech site admitted to the UNESCO Global Geoparks Network in recognition of its geological and landscape value.