Trupelník is a small but fascinating hill near the town of Bílina, prized by nature lovers and geology enthusiasts alike. This nature reserve protects one of the region's most important paleontological sites along with rare warmth-loving plant communities.

The hill's landscape is defined by its so-called white slopes, standing out sharply against the surrounding green fields and forests. A dry, sun-exposed microclimate here has allowed rare and endangered plants, such as spring pheasant's eye and yellow flax, to survive. In spring and summer the slopes bloom with colorful rare flowers, while in autumn and winter the hill reveals its geological layers - diatomite earth and a basalt cap visible in several outcrops.

• From Bílina - local trail, approx. 30-40 minutes, easy difficulty
• Accessible also via nearby field roads, suitable for a short afternoon walk

• Protected nature reserve - collecting plants or minerals is prohibited
• Significant paleontological site of Eocene lake sediments - diatomite earth and fossils
• A crevice filled with gypsum crystals has been recorded on the northern slope

Interesting fact: some of the rare plants growing here were transplanted in the 1980s from the Bělák site, which was destroyed by the Radovesice spoil heap - Trupelník became their new refuge.