Borschen

The Bořeň is a 539-metre phonolite rock mountain south of Bílina in the Bohemian Central Highlands, considered the largest phonolite monolith in Central Europe. Its silhouette resembles a recumbent lion — earning it the local nickname 'Biliner Löwe' (Bilin Lion). The mountain was designated a National Nature Reserve in 1977, protecting 23.4 hectares of its distinctive stepped basalt-like cliffs, which rise up to 100 metres vertically. Phonolite, also called klangstein (ringing stone) for the metallic sound it produces when struck, formed as a volcanic intrusion whose hard core remained after softer surrounding rock eroded away. Today the sheer, structured faces are an established climbing area with routes across multiple grades, and the summit offers broad views over the North Bohemian basin and its characteristic table mountains.